View source for Hyphen

{{Short description|Punctuation mark used to join words}}
{{About|the punctuation mark}}
{{Use dmy dates|date=May 2020}}
{{Infobox punctuation mark
|mark=‐|name=Hyphen
|variant1=-|caption1=Hyphen-minus
|variant2=‑|caption2=Non-breaking hyphen
}}

The '''hyphen''' '''{{char|‐}}''' is a [[punctuation]] mark used to join [[word]]s and to separate [[syllable]]s of a single word. The use of hyphens is called '''hyphenation'''.<ref>{{cite dictionary|url=http://dictionary.reference.com/browse/hyphen|title=''Hyphen'' Definition|dictionary=[[dictionary.com]]|access-date=18 June 2015}}</ref>

The hyphen is sometimes confused with [[dash]]es ([[en dash]] {{char|–}}, [[em dash]] {{char|—}} and others), which are wider, or with the [[minus sign]] {{char|−}}, which is also wider and usually drawn a little higher to match the crossbar in the [[plus sign]] {{char|+}}.

As an [[Orthography|orthographic]] concept, the hyphen is a single entity. In [[character encoding]] for use with computers, it is represented in [[Unicode]] by any of several [[character (computing)|characters]]. These include the dual-use [[hyphen-minus]], the [[soft hyphen]], the [[#Nonbreaking hyphens|nonbreaking hyphen]], and an unambiguous form known familiarly as the "Unicode hyphen", shown at the top of the infobox on this page. The character most often used to represent a hyphen (and the one produced by the key on a keyboard) is called the "hyphen-minus" in the Unicode specification because it is also used as a [[minus sign]]. The name derives from its name in the original [[ASCII]] standard, where it was called "hyphen{{nbsp}}(minus)".<ref>{{cite web |title=American National Standard X3.4-1977: American Standard Code for Information Interchange | page=10 (4.2 Graphic characters) |url=https://nvlpubs.nist.gov/nistpubs/Legacy/FIPS/fipspub1-2-1977.pdf |publisher=National Institute of Standards and Technology}}</ref>

== Etymology ==
The word is derived from Ancient Greek {{lang|grc|ὑφ' ἕν}} ({{transliteration|grc|huph' hén}}), contracted from {{lang|grc|ὑπό ἕν}} ({{transliteration|grc|hypó hén}}), "in one" (literally "under one").<ref>{{LSJ|u%28fe%2Fn|ὑφέν|ref}}.</ref><ref>{{OEtymD|hyphen}}</ref> An {{lang|grc|(ἡ) ὑφέν}} ({{transliteration|grc|(he) hyphén}}) was an [[undertie]]-like {{char|‿}} sign written below two adjacent letters to indicate that they belong to the same word when it was necessary to avoid ambiguity, before [[Word divider|word spacing]] was practiced.

== History<span class="anchor" id="Origin and history"></span> ==
[[File:Gutenberg bible Old Testament Epistle of St Jerome.jpg|thumb|First page of the first volume: the [[Jerome's epistle to Paulinus (Gutenberg Bible preface)|epistle of St Jerome to Paulinus]] from the University of Texas copy. The page has 40 lines.]]
The first known documentation of the hyphen is in the grammatical works of [[Dionysius Thrax]]. At the time hyphenation was joining two words that would otherwise be read separately by a low [[tie (typography)|tie mark]] between the two words.<ref name="nicky">Nicolas, Nick. "[http://www.tlg.uci.edu/~opoudjis/unicode/punctuation.html Greek Unicode Issues: Punctuation] {{webarchive|url=https://archive.today/20120806003722/http://www.tlg.uci.edu/~opoudjis/unicode/punctuation.html|date=6 August 2012}}". 2005. Accessed 7 October 2014.</ref> In Greek these marks were known as ''[[enotikon]]'', officially [[romanization of Greek|romanized]] as a hyphen.<ref name="elot">{{lang|el|Ελληνικός Οργανισμός Τυποποίησης}} [''Ellīnikós Organismós Typopoíīsīs'', "[[Hellenic Organization for Standardization]]"]. {{lang|el|ΕΛΟΤ 743, 2η Έκδοση}} [''ELOT 743, 2ī Ekdosī'', "ELOT 743, {{nowrap|2nd ed.}}"]. ELOT (Athens), 2001. {{in lang|el}}</ref>

With the introduction of [[letter spacing]] in the [[Middle Ages]], the hyphen, still written beneath the text, reversed its meaning. Scribes used the mark to connect two words that had been incorrectly separated by a space. This era also saw the introduction of the marginal hyphen, for words broken across lines.<ref name="Houston2013">{{cite book |author=Keith Houston |url=https://books.google.com/books?id=3fbWAAAAQBAJ&pg=PA132 |title=Shady Characters: The Secret Life of Punctuation, Symbols, and Other Typographical Marks |publisher=W.W. Norton & Company |year=2013 |isbn=978-0-393-06442-1 |page=121}}</ref>

The modern format of the hyphen originated with [[Johannes Gutenberg]] of Mainz, Germany, {{circa|lk=no|1455}} with the publication of his 42-line [[Gutenberg Bible|Bible]]. His tools did not allow for a [[wikt:sublinear|sublinear]] hyphen, and he thus moved it to the middle of the line.<ref name="Houston2013b">{{cite book |author=Keith Houston |url=https://books.google.com/books?id=3fbWAAAAQBAJ&pg=PA132 |title=Shady Characters: The Secret Life of Punctuation, Symbols, and Other Typographical Marks |publisher=W.W. Norton & Company |year=2013 |isbn=978-0-393-06442-1 |page=132}}</ref> Examination of an original copy on [[vellum]] (Hubay index #35) in the [[Library of Congress|U. S. Library of Congress]] shows that Gutenberg's movable type was set justified in a uniform style, 42 equal lines per page. The Gutenberg printing press required words composed of individual movable type to be secured within a rigid, nonprinting frame. To ensure each line fit the frame uniformly, Gutenberg addressed differences in line length by inserting a hyphen at the end of a line at the right-hand margin. This interrupted the letters in the last word, requiring the remaining letters be carried over to the start of the line below. His [[double hyphen]], <big>{{char|⸗}}</big>, appears throughout the Bible as a short, double line inclined to the right at a 60-degree angle.{{Citation needed|date=September 2021}}

== Use in English ==
{{For|Wikipedia's own standards for hyphen use|Wikipedia:Manual of Style#Hyphens|selfref=true}}
{{Original research section|date=January 2016|reason=Almost nothing in this section is tied to reliable sources, and there's a great deal of prescriptivist punditry about "codification" of various "rules".}}

The [[English language]] does not have definitive hyphenation rules,<ref name="Economist intro">{{cite book |title=The Economist Style Guide |edition=11th |date=2015 |editor-first=Ann |editor-last=Wroe |location=London / New York |publisher=Profile Books / PublicAffairs |page=74 |quote='''hyphens'''&nbsp;&nbsp;There is no firm rule to help you decide which words are run together, hyphenated or left separate.}}</ref> though various [[style guide]]s provide detailed usage recommendations and have a significant amount of overlap in what they advise. Hyphens are mostly used to break single words into parts or to join ordinarily separate words into single words. Spaces are not placed between a hyphen and either of the elements it connects except when using a suspended or "hanging" hyphen that stands in for a repeated word (e.g., ''nineteenth- and {{nowrap|twentieth-century}} writers''). Style conventions that apply to hyphens (and dashes) have evolved to support ease of reading in complex constructions; editors often accept deviations if they aid rather than hinder easy comprehension.

The use of the hyphen in [[English compound]] nouns and verbs has, in general, been steadily declining. Compounds that might once have been hyphenated are increasingly left with spaces or are combined into one word. Reflecting this changing usage, in 2007, the sixth edition of the ''[[Shorter Oxford English Dictionary]]'' removed the hyphens from 16,000&nbsp;entries, such as ''fig-leaf'' (now ''fig leaf''), ''pot-belly'' (now ''pot belly''), and ''pigeon-hole'' (now ''pigeonhole'').<ref>{{cite web |url= https://news.bbc.co.uk/1/hi/magazine/7004661.stm |title=Small object of grammatical desire |publisher=[[British Broadcasting Corporation]] |work=[[BBC News]] |location=London |date=20 September 2007}}.</ref> The increasing prevalence of computer technology and the advent of the Internet have given rise to a subset of common nouns that might have been hyphenated in the past (e.g., ''[[toolbar]]'', ''[[hyperlink]]'', and ''[[pastebin]]'').

Despite decreased use, hyphenation remains the norm in certain compound-modifier constructions and, among some authors, with certain prefixes (see [[#Prefixes_and_suffixes|below]]). Hyphenation is also routinely used as part of [[syllabification]] in [[typographic alignment#Justified|justified]] texts to avoid unsightly spacing (especially in [[column (typography)|columns]] with narrow [[line length]]s, as when used with [[newspaper]]s).

=== Separating ===
==== Justification and line-wrapping ====
When flowing text, it is sometimes preferable to break a word into two so that it continues on another line rather than moving the entire word to the next line. The word may be divided at the nearest break point between syllables ([[syllabification]]) and a hyphen inserted to indicate that the letters form a word fragment, rather than a full word. This allows more efficient use of paper, allows flush appearance of right-side margins ([[typographic alignment#Justified|justification]]) without oddly large word spaces, and decreases the problem of [[river (typography)|rivers]]. This kind of hyphenation is most useful when the width of the column (called the "line length" in typography) is very narrow. For example:

{|
|- valign="top"
| ''Justified text<br />without hyphenation''
|
| ''Justified text<br />with hyphenation''
|- valign="top"
| style="font-family: monospace; text-align: justify"|
We,&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;therefore,&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;the<br />
representatives of the United<br />
States of America ...
| style=width:3em;|&nbsp;&nbsp;
| style="font-family: monospace; text-align: justify;"|
We,&nbsp;therefore,&nbsp;the&nbsp;{{not a typo|represen-}}<br />
tatives of&nbsp;the United States <br />
of America ...
|}

Rules (or guidelines) for correct hyphenation vary between languages, and may be complex, and they can interact with other [[Orthography|orthographic]] and [[typesetting]] practices. [[Hyphenation algorithm]]s, when employed in concert with dictionaries, are sufficient for all but the most formal texts.

It may be necessary to distinguish an incidental line-break hyphen from one integral to a word [[use–mention distinction|being mentioned]] (as when used in a [[dictionary]]) or present in an original text being quoted (when in a [[critical edition]]), not only to control its [[word wrap]] behavior (which [[character encoding|encoding]] handles with [[#Soft and hard hyphens|hard and soft hyphens]] having the same [[glyph]]) but also to differentiate appearance (with a different glyph). ''[[Webster's Third New International Dictionary]]''<ref name="Gove1993">{{cite book|last=Gove|first=Philip Babcock|title=Webster's Third New International Dictionary of the English Language, Unabridged|url=https://books.google.com/books?id=CXR-tTsHo58C&pg=PT23|access-date=28 November 2014|year=1993|publisher=Merriam-Webster|isbn=978-0-87779-201-7|page=14a, §&nbsp;1.6.1}}</ref> and the ''[[Chambers Dictionary]]''<ref name="Chambers2006">{{cite book|last=Chambers|first=Allied|title=The Chambers Dictionary|url=https://books.google.com/books?id=pz2ORay2HWoC&pg=PP38|access-date=28 November 2014|year=2006|publisher=Allied Publishers|isbn=978-8186062258|page=xxxviii, §&nbsp;8}}</ref> use a [[double hyphen]] for integral hyphens and a single hyphen for line-breaks, whereas Kromhout's Afrikaans–English dictionary uses the opposite convention.<ref name="Kromhout2001">{{cite book|last=Kromhout|first=Jan|title=Afrikaans–English, English–Afrikaans Dictionary|url=https://archive.org/details/afrikaansenglish00krom|url-access=registration|access-date=28 November 2014|year=2001|publisher=Hippocrene Books|isbn=978-0-7818-0846-0|page=[https://archive.org/details/afrikaansenglish00krom/page/182 182], §&nbsp;5}}</ref> The ''[[Concise Oxford Dictionary]] (fifth edition)'' suggested repeating an integral hyphen at the start of the following line.<ref name="Hartmann1986">{{cite book|last=Hartmann|first=R. Rf. K.|title=The History of Lexicography: Papers from the Dictionary Research Centre Seminar at Exeter, March 1986|url=https://books.google.com/books?id=cKT4L5Qg7ZkC&pg=PA9|year=1986|publisher=John Benjamins Publishing|isbn=978-9027245236|page=9}}</ref>

==== Prefixes and suffixes ====
[[Prefix]]es (such as ''de-'', ''pre-'', ''re-'', and ''non-''<ref name="footnote_prefix_list">A fairly comprehensive list, although not exhaustive, is given at [[Prefix#List of English derivational prefixes|Prefix > List of English derivational prefixes]].</ref>) and [[suffix]]es (such as ''{{nowrap|-less}}'', ''{{nowrap|-like}}'', ''{{nowrap|-ness}}'', and ''{{nowrap|-hood}}'') are sometimes hyphenated, especially when the unhyphenated spelling resembles another word or when the [[affix]]ation is deemed misinterpretable, ambiguous, or somehow "odd-looking" (for example, having two consecutive [[phonemic orthography|monograph]]s that look like the [[Digraph (orthography)|digraph]]s of English, like e+a, e+e, or e+i). However, the unhyphenated style, which is also called ''closed up'' or ''solid'', is usually preferred, particularly when the [[Derivation (linguistics)|derivative]] has been relatively familiarized or popularized through extensive use in various contexts. As a [[rule of thumb]], affixes are not hyphenated unless the lack of a hyphen would hurt clarity.

The hyphen may be used between vowel letters (e.g., ''ee'', ''ea'', ''ei'') to indicate that they do not form a [[Digraph (orthography)|digraph]]. Some words have both hyphenated and unhyphenated variants: ''{{nowrap|de-escalate}}/deescalate'', ''{{nowrap|co-operation}}/cooperation'', ''{{nowrap|re-examine}}/reexamine'', ''{{nowrap|de-emphasize}}/deemphasize'', and so on. Words often lose their hyphen as they become more common, such as ''[[email]]'' instead of ''{{nowrap|e-mail}}''. When there are tripled letters, the hyphenated variant of these words is often more common (as in ''{{nowrap|shell-like}}'' instead of ''{{not a typo|shelllike}}'').

Closed-up style is avoided in some cases: possible [[homograph]]s, such as ''[[recreation]]'' (fun or sport) versus ''{{nowrap|re-creation}}'' (the act of creating again), ''retreat'' (turn back) versus ''{{nowrap|re-treat}}'' (give [[therapy]] again), and ''{{nowrap|un-ionized}}'' (not in [[ion]] form) versus ''unionized'' (organized into [[trade union]]s); combinations with [[proper noun|proper]] nouns or adjectives (''{{nowrap|un-American}}'', ''{{nowrap|de-Stalinisation}}'');<ref>{{Citation | url = http://www.grammarmudge.cityslide.com/articles/article/426348/2805.htm | contribution = Hyphenated Words: A Guide | title = The Grammar Curmudgeon | publisher = City slide}}.</ref><ref name="Grammar book">{{Citation | url = http://www.grammarbook.com/punctuation/hyphens.asp | title = Punctuation | publisher = Grammar book | contribution = Hyphens}}.</ref> [[acronym]]s (''{{nowrap|anti-TNF antibody}}'', ''{{nowrap|non-SI units}}''); or numbers (''{{nowrap|pre-1949 diplomacy}}'', ''{{nowrap|pre-1492 cartography}}''). Although ''{{nowrap|[[proto-oncogene]]}}'' is still hyphenated by both ''Dorland's'' and ''Merriam-Webster's Medical'', the solid (that is, unhyphenated) styling (''protooncogene'') is a common variant, particularly among oncologists and geneticists.{{citation needed|date=September 2021}}

A [[diaeresis (diacritic)|diaeresis]] may also be used in a like fashion, either to separate and mark off monographs (as in ''coöperation'') or to signalize a [[vowel|vocalic]] terminal e (for example, ''[[Brontë family|Brontë]]''). This use of the diaeresis peaked in the late 19th and early 20th centuries, but it was never applied extensively across the language: only a handful of diaereses, including ''coöperation'' and ''Brontë'', are encountered with any appreciable frequency in English; thus ''reëxamine'', ''reïterate'', ''deëmphasize'', etc. are seldom encountered. In borrowings from Modern French, whose [[French orthography|orthography]] utilizes the diaeresis as a means to differentiate [[grapheme]]s, various English dictionaries list the dieresis as optional (as in ''naive'' and ''naïve'') despite the juxtaposition of a and i.{{citation needed|date=September 2021}}

==== Syllabification and spelling ====
Hyphens are occasionally used to denote [[syllabification]], as in ''syl-la-bi-fi-ca-tion''. Various British and North American dictionaries use an [[interpunct]] (sometimes called a "middle dot" or "hyphenation point"), for this purpose, as in ''syl·la·bi·fi·ca·tion''. This practice allows the hyphen to be reserved exclusively for instances where a true hyphen is intended{{snd}} for example, ''self-con·scious'', ''un·self-con·scious'', and ''long-stand·ing''. Similarly, hyphens may be used to indicate the spelling of a word, as in ''W-O-R-D'' to represent ''word''.

In nineteenth-century American literature, hyphens were also used irregularly to divide syllables in words from indigenous North American languages, without regard for etymology or pronunciation,<ref>{{Cite web|last=Liberman|first=Mark|title=American Indian Hyphens|url=http://itre.cis.upenn.edu/~myl/languagelog/archives/005174.html|website=Language Log}}</ref> such as "Shuh-shuh-gah" (from [[Ojibwe language|Ojibwe]] ''zhashagi'', "blue heron") in ''[[The Song of Hiawatha]]''.<ref>{{Cite book|last=Longfellow|first=Henry Wadsworth|url=https://www.gutenberg.org/files/19/19-h/19-h.htm|title=The Song of Hiawatha}}</ref> This usage is now rare and deprecated,{{cn|date=July 2025}} except in some place names such as [[Ah-gwah-ching, Minnesota|Ah-gwah-ching]].

=== Joining ===
==== Compound modifiers ====
{{Further|Compound modifier|English compound#Hyphenated compound modifiers}}

[[Compound modifier]]s are groups of two or more words that jointly modify the meaning of another word. When a compound modifier other than an [[adverb]]–[[adjective]] combination appears ''before'' a term, the compound modifier is often hyphenated to prevent misunderstanding, such as in ''{{nowrap|American-football}} player'' or ''{{nowrap|little-celebrated}} paintings''. Without the hyphen, there is potential confusion about whether the writer means a "player of American football" or an "American player of football" and whether the writer means paintings that are "little celebrated" or "celebrated paintings" that are little.<ref>[[Gary Blake]] and [[Robert W. Bly]], ''The Elements of Technical Writing'', p. 48. [[New York City|New York]]: [[Macmillan Publishers (United States)|Macmillan Publishers]], 1993. {{ISBN|0020130856}}</ref> Compound modifiers can extend to three or more words, as in ''{{nowrap|ice-cream-flavored}} candy'', and can be adverbial as well as adjectival (''{{nowrap|spine-tinglingly}} frightening''). However, if the compound is a familiar one, it is usually unhyphenated. For example, some style guides prefer the construction ''high school students'', to ''{{nowrap|high-school}} students''.<ref>E.g. {{cite web |url= https://www.jhsph.edu/news/style_manual/h.html |title=H |work=Bloomberg School Style Manual |publisher=Johns Hopkins Bloomberg School of Public Health |access-date=9 March 2019}}</ref><ref name="IU Style Guide" /> Although the expression is technically ambiguous ("students of a high school"/"school students who are high"), it would normally be formulated differently if other than the first meaning were intended. Noun–noun compound modifiers may also be written without a hyphen when no confusion is likely: ''grade point average'' and ''department store manager''.<ref name="IU Style Guide" />

When a compound modifier ''follows'' the term to which it applies, a hyphen is typically not used if the compound is a temporary compound. For example, "that gentleman is well respected", not "that gentleman is well-respected"; or "a patient-centered approach was used" but "the approach was patient centered."<ref>{{cite web|url=http://www.uhv.edu/ac/newsletters/writing/grammartip2004.11.30.htm |archive-url=https://web.archive.org/web/20100109235952/http://www.uhv.edu/ac/newsletters/writing/grammartip2004.11.30.htm |url-status = dead|archive-date=9 January 2010 |publisher=UHV |type=Grammar tip |date=2004-11-30 |title=Using Hyphens in Compound Adjectives (and Exceptions to the Rule) |first=John |last=Davis |access-date=2010-01-05}}</ref> But permanent compounds, found as headwords in dictionaries, are treated as invariable, so if they are hyphenated in the cited dictionary, the hyphenation will be used in both attributive and predicative positions. For example, "A cost-effective method was used" and "The method was cost-effective" (''cost-effective'' is a permanent compound that is hyphenated as a headword in various dictionaries). When one of the parts of the modifier is a [[proper noun]] or a [[proper adjective]], there is no hyphen (e.g., "a South American actor").<ref name="Hyphenated Compound Words">{{cite web|url = http://englishplus.com/grammar/00000127.htm|title = Hyphenated Compound Words|access-date = 2014-11-18|website = englishplus.com}}</ref>

When the first modifier in a compound is an adverb ending in ''-ly'' (e.g., "a poorly written novel"), various style guides advise no hyphen.<ref name="Hyphenated Compound Words" />{{additional citation needed|date=January 2016}} However, some do allow for this use. For example, ''[[The Economist]] Style Guide'' advises: "Adverbs do not need to be linked to participles or adjectives by hyphens in simple constructions{{nbsp}}... Less common adverbs, including all those that end ''-ly'', are less likely to need hyphens."<ref name="Economist 12">{{cite book |title=The Economist Style Guide |edition=11th |date=2015 |editor-first=Ann |editor-last=Wroe |location=London / New York |publisher=Profile Books / PublicAffairs |pages=77–78 |quote='''hyphens'''&nbsp;&nbsp; ... 12. Adverbs: Adverbs do not need to be linked to participles or adjectives by hyphens in simple constructions [examples elided]. But if the adverb is one of two words together being used adjectivally, a hyphen may be needed [examples elided]. The hyphen is especially likely to be needed if the adverb is short and common, such as ''ill'', ''little'', ''much'' and ''well''. Less common adverbs, including all those that end ''-ly'', are less likely to need hyphens [example elided].}}</ref> In the 19th century, it was common to hyphenate adverb–adjective modifiers with the adverb ending in ''-ly'' (e.g., "a craftily-constructed chair"). However, this has become rare. For example, ''wholly owned subsidiary'' and ''quickly moving vehicle'' are unambiguous, because the adverbs clearly modify the adjectives: "quickly" cannot modify "vehicle".

However, if an adverb can also function as an adjective, then a hyphen may be or should be used for clarity, depending on the style guide.<ref name="Grammar book" /> For example, the phrase ''{{nowrap|more-important}} reasons'' ("reasons that are more important") is distinguished from ''more important reasons'' ("additional important reasons"), where ''more'' is an adjective. Similarly, ''{{nowrap|more-beautiful}} scenery'' (with a [[mass noun|mass-noun]]) is distinct from ''more beautiful scenery''. (In contrast, the hyphen in "a {{nowrap|more-important}} reason" is not necessary, because the syntax cannot be misinterpreted.) A few short and common words—such as ''well'', ''ill'', ''little'', and ''much''—attract special attention in this category.<ref name="Economist 12" /> The hyphen in "well-[past_participled] noun", such as in "[[Cellular differentiation|well-differentiated cells]]", might reasonably be judged superfluous (the syntax is unlikely to be misinterpreted), yet plenty of style guides call for it. Because ''early'' has both adverbial and adjectival senses, its hyphenation can attract attention; some editors, due to comparison with ''advanced-stage disease'' and ''adult-onset disease'', like the parallelism of ''early-stage disease'' and ''early-onset disease''. Similarly, the hyphen in ''little-celebrated paintings'' clarifies that one is not speaking of little paintings.

Hyphens are usually used to connect numbers and words in modifying phrases. Such is the case when used to describe dimensional measurements of weight, size, and time, under the rationale that, like other compound modifiers, they take hyphens in attributive position (before the modified noun),<ref name="AMA10section8.3.1">{{cite book |last=Iverson |first=Cheryl|title=AMA Manual of Style |edition=10th |publisher=[[Oxford University Press]] |location=Oxford, Oxfordshire |year=2007 |isbn=978-0-19-517633-9 |section=8.3.1 |url=https://archive.org/details/amamanualofstyle0000unse }}</ref> although not in predicative position (after the modified noun). This is applied whether numerals or words are used for the numbers. Thus ''{{nowrap|28-year-old}} woman'' and ''{{nowrap|twenty-eight-year-old}} woman'' or ''{{nowrap|32-foot}} wingspan'' and ''{{nowrap|thirty-two-foot}} wingspan'', but ''the woman is 28 years old'' and ''a wingspan of 32 feet''.{{efn|name=Plural nouns|With numbers, where a plural noun would normally be used in an unhyphenated predicative position, the singular form of the noun is generally used in the hyphenated form used attributively. Thus ''a woman who is 28 years old'' becomes ''a {{nowrap|28-year-old}} woman''. There are occasional exceptions to this general rule, for instance with fractions (''a two-thirds majority'') and irregular plurals (''a two-criteria review'', ''a two-teeth bridge'').}} However, with symbols for [[SI]] units (such as ''[[metre|m]]'' or ''[[kilogram|kg]]'')—in contrast to the ''names'' of these units (such as ''[[metre]]'' or ''[[kilogram]]'')—the numerical value is always separated from it with a space: ''a 25&nbsp;kg sphere''. When the unit names are spelled out, this recommendation does not apply: ''a {{nowrap|25-kilogram}} sphere'', ''a roll of {{nowrap|35-millimetre}} film''.<ref>Bureau international des poids et mesures, [https://www.bipm.org/utils/common/pdf/si-brochure/SI-Brochure-9.pdf#page=151 ''Le Système international d'unités (SI) / The International System of Units (SI)'', 9th ed.] (Sèvres: 2019), {{ISBN|978-92-822-2272-0|invalid1=yes}}, sub§5.4.3, p. 149; [http://physics.nist.gov/cuu/pdf/sp811.pdf "Guide for the Use of the International System of Units (SI)"], NIST Special Publication 811, [[National Institute of Standards and Technology]], March 2008.</ref>

In spelled-out [[fraction (mathematics)|fractions]], hyphens are usually used when the fraction is used as an adjective but not when it is used as a noun: thus ''{{nowrap|two-thirds}} majority''{{efn|name=Plural nouns}} and ''{{nowrap|one-eighth}} portion'' but ''I drank two thirds of the bottle'' or ''I kept three quarters of it for myself''.<ref name="APA6section4.13">{{Citation |author=American Psychological Association (APA) |author-link=American Psychological Association |year=2010 |title=The Publication Manual of the American Psychological Association |edition=6th |publisher=American Psychological Association |location=Washington, DC|isbn=978-1-4338-0562-2 |url=http://apastyle.org/ |postscript=.}}</ref> However, at least one major style guide<ref name="AMA10section8.3.1" /> hyphenates spelled-out fractions invariably (whether adjective or noun).

In English, {{Anchor|En dash, hyphen, or either one}} an [[en dash]], {{char|–}}, sometimes replaces the hyphen in hyphenated compounds if either of its constituent parts is already hyphenated or contains a space (for example, ''San Francisco–area residents'', ''hormone receptor–positive cells'', ''cell cycle–related factors'', and ''public-school–private-school rivalries'').<ref name="LutzStevenson2005">{{cite book|author1=Gary Lutz|author2=Diane Stevenson|title=The Writer's Digest grammar desk reference|url=https://books.google.com/books?id=SsQ9ugnMcpUC&pg=PA296|year=2005|publisher=Writer's Digest Books|isbn=978-1-58297-335-7|page=296}}</ref> A commonly used alternative style is the hyphenated string (''hormone-receptor-positive cells'', ''cell-cycle-related factors''). (For other aspects of en dash–versus–hyphen use, see ''[[Dash#En dash|Dash § En dash]]''.)

==== Object–verbal-noun compounds ====
{{anchor|Object–verbal noun compounds||reason=Old section name; lots of redirs point here.}}

When an object is compounded with a verbal noun, such as ''[[Mixer (cooking)|egg-beater]]'' (a tool that beats eggs), the result is sometimes hyphenated. Some authors do this consistently, others only for disambiguation; in this case, ''egg-beater, egg beater,'' and ''eggbeater'' are all common.

An example of an ambiguous phrase appears in ''they stood near a group of alien lovers'', which without a hyphen implies that they stood near a group of lovers who were aliens; ''they stood near a group of alien-lovers'' clarifies that they stood near a group of people who loved aliens, as "alien" can be either an adjective or a noun. On the other hand, in the phrase ''a hungry pizza-lover'', the hyphen will often be omitted (a hungry pizza lover), as "pizza" cannot be an adjective and the phrase is therefore unambiguous.

Similarly, ''a man-eating shark'' is nearly the opposite of ''a man eating shark''; the first refers to a shark that eats people, and the second to a man who eats [[shark meat]]. ''A government-monitoring program'' is a program that monitors the government, whereas ''a government monitoring program'' is a government program that monitors something else.

==== Personal names ====
{{See also|Spanish naming customs#Hyphenation|Portuguese name#Hyphenation}}

Some married couples compose a new [[surname]] (sometimes referred to as a [[double-barrelled name]]) for their new family by combining their two surnames with a hyphen. Jane Doe and John Smith might become Jane and John Smith-Doe, or Doe-Smith, for instance. In some countries only the woman hyphenates her birth surname, appending her husband's surname.

With already-hyphenated names, some parts are typically dropped. For example, Aaron Johnson and Samantha Taylor-Wood became [[Aaron Taylor-Johnson]] and [[Sam Taylor-Johnson]]. Not all hyphenated surnames are the result of marriage. For example [[Julia Louis-Dreyfus]] is a descendant of Louis Lemlé Dreyfus whose son was Léopold Louis-Dreyfus.

Hyphens are often used in romanization of [[Korean names]], such as [[Ban Ki-moon]] and [[Cho Jung-ho]].

==== Other compounds ====
Connecting hyphens are used in a large number of miscellaneous compounds, other than modifiers, such as in ''lily-of-the-valley'', ''cock-a-hoop'', ''clever-clever'', ''tittle-tattle'' and ''orang-utan''. Use is often dictated by convention rather than fixed rules, and hyphenation styles may vary between authors; for example, ''orang-utan'' is also written as ''orangutan'' or ''orang utan'', and ''lily-of-the-valley'' may be hyphenated or not.

==== Suspended hyphens ====
{{anchor|Suspended hyphens}}<!-- Section header used as link target in redirects -->

A '''suspended hyphen''' (also called a '''suspensive hyphen''' or '''hanging hyphen''', or less commonly a '''dangling''' or '''floating hyphen''') may be used when a single base word is used with separate, consecutive, hyphenated words that are connected by "and", "or", or "to". For example, ''short-term and long-term plans'' may be written as ''short- and long-term plans.'' This usage is now common and specifically recommended in some style guides.<ref name="IU Style Guide">E.g. {{cite web |url=https://brand.iu.edu/messaging-strategy/editorial-style/style-guide/h.html |title=H |work=The IU editorial style guide |publisher=Indiana University |access-date=9 March 2019 |archive-date=14 June 2019 |archive-url=https://web.archive.org/web/20190614170302/https://brand.iu.edu/messaging-strategy/editorial-style/style-guide/h.html |url-status=dead }}</ref> Suspended hyphens are also used, though less commonly, when the base word comes first, such as in "investor-owned and {{nowrap|-operated}}". Uses such as "applied and sociolinguistics" (instead of "applied linguistics and sociolinguistics") are frowned upon; the Indiana University style guide uses this example and says "Do not 'take a shortcut' when the first expression is ordinarily open" (i.e., ordinarily two separate words).<ref name="IU Style Guide" /> This is different, however, from instances where prefixes that are normally closed up (styled solidly) are used suspensively. For example, ''{{nowrap|preoperative and postoperative}}'' becomes ''{{nowrap|pre- and postoperative}}'' (not ''{{nowrap|pre- and post-operative}}'') when suspended. Some editors prefer to avoid suspending such pairs, choosing instead to write out both words in full.<ref name="AMA10section8.3.1" />

=== Other uses ===
A hyphen may be used to connect groups of numbers, such as in [[Calendar date|dates]] (see [[Hyphen#Use in date notation|§ Usage in date notation]]), [[Telephone number|telephone numbers]] or sports [[Score (game)|scores]].

It can also be used to indicate a range of values, although many styles prefer an en dash (see {{mslink|Dash|En dash|Ranges of values}}).

It is sometimes used to hide letters in words ([[fillet (redaction)|filleting for redaction or censoring]]), as in "[[G-d]]", although an en dash can be used as well ("G–d").<ref>{{Cite web |last=Davidson |first=Baruch |date=2011-02-23 |title=Why Don't Jews Say G‑d's Name? - On the use of the word "Hashem" - Chabad.org |url=https://www.chabad.org/library/article_cdo/aid/1443443/jewish/Why-Dont-Jews-Say-Gds-Name.htm |access-date=2023-04-15 |website=[[Chabad.org]] |quote=It is customary to insert a dash in G-d's name when written or printed on a medium that could be defaced.}}</ref>

It is often used in [[reduplication]].<ref>{{Cite web |date=2013-09-26 |title=Like vs. Like-Like: A Look at Reduplication in English |url=https://www.dictionary.com/e/reduplication/ |access-date=2023-04-15 |website=[[Dictionary.com]] |language=en-US}}</ref>

Due to their similar appearances, hyphens are sometimes mistakenly used where an en dash or em dash would be more appropriate.<ref>{{Cite news |last=Gunner |first=Jennifer |date=2010-02-22 |title=When and How To Use a Hyphen ( - ) |url=https://grammar.yourdictionary.com/punctuation/hyphen-rules.html |access-date=2023-04-15 |website=grammar.yourdictionary.com |language=en |quote=Many people confuse hyphens and dashes because they look similar in printing.}}</ref>

=== Varied meanings ===
Some stark examples of semantic changes caused by the placement of hyphens to mark attributive phrases:
* ''Disease-causing poor nutrition'' is poor nutrition that causes disease.
** ''Disease causing poor nutrition'' is a disease that causes poor nutrition.
* A ''hard-working man'' is a man who works hard.
** A ''hard working man'' is a working man who is tough; however, this sense of ''hard'' is rarely used before other adjectives.
* A ''man-eating shark'' is a shark that eats humans.
** A ''man eating shark'' is a man who is eating shark meat.
* ''Three-hundred-year-old trees'' are an indeterminate number of trees that are each 300 years old.
** ''Three hundred-year-old trees'' are three trees that are each 100 years old.
** ''Three hundred year-old trees'' are 300 trees that are each a year old.

== Use in computing<span class="anchor" id="In computing"></span> ==
{{Refimprove section|date=November 2020}}

=== Hyphen-minuses ===
{{Main|Hyphen-minus}}

In the [[ASCII]] character encoding, the hyphen (or minus) is character 45<sub>10</sub>.<ref>{{cite book |last=Haralambous |first=Yannis |title=Fonts & Encodings |publisher=O'Reilly Media |date=2007 |isbn=978-0596102425 |page=29 |chapter=ASCII}}</ref> As [[Unicode]] is identical to ASCII (the 1967 version) for all encodings up to 127<sub>10</sub>, the number 45<sub>10</sub> (2D<sub>16</sub>) is also assigned to this character in Unicode, where it is denoted as {{nowrap|{{unichar|002D|HYPHEN-MINUS}}}}.<ref>{{cite book |title=Unicode Version 1.0 · Character Blocks |page=30 |chapter-url= https://www.unicode.org/versions/Unicode1.0.0/ch03_1.pdf |chapter=3.1 General scripts |quote='''Loose vs. Precise Semantics.''' Some ASCII characters have multiple uses, either through ambiguity in the original standards or through accumulated reinterpretations of a limited codeset. For example, 27 hex is defined in ANSI X3.4 as apostrophe (closing single quotation mark; acute accent), and 2D hex as hyphen minus.}}</ref> Unicode has, in addition, other encodings for minus and hyphen characters: {{nowrap|{{unichar|2212|minus sign}}}} and {{nowrap|{{unichar|2010|hyphen}}}}, respectively. The unambiguous {{slink||"Unicode hyphen"}} at U+2010 is generally inconvenient to enter on most keyboards and the glyphs for this hyphen and the hyphen-minus are identical in most fonts ([[Lucida Sans Unicode]] is one of the few exceptions). Consequently, use of the hyphen-minus as the hyphen character is very common. Even the [[Unicode Standard]] regularly uses the hyphen-minus rather than the U+2010 hyphen.

The hyphen-minus has limited use in indicating subtraction; for example, compare {{char|1=4+3−2=5}} (minus) and {{char|1=4+3-2=5}} (hyphen-minus) — in most typefaces, the [[glyph]] for hyphen-minus will not have the optimal width, thickness, or vertical position, whereas the minus character is typically designed so that it does. Nevertheless, in many spreadsheet and programming applications the hyphen-minus must be typed to indicate subtraction, as use of the Unicode minus sign will not be recognised.

The hyphen-minus is often used instead of dashes or minus signs in situations where the latter characters are unavailable (such as [[type writer|type-written]] or ASCII-only text), where they take effort to enter (via [[dialog box]]es or multi-key [[keyboard shortcut]]s), or when the writer is unaware of the distinction. Consequently, some writers use two or three hyphen-minuses ({{code|--}} or {{code|---}}) to represent an em dash.<ref>{{cite book |title = The elements of typographic style |edition = third |first = Robert |last = Bringhurst |publisher = Hartley & Marks, Publishers |year = 2004 |isbn = 978-0-88179-206-5 |page = 80  |access-date = 10 November 2020  |url=https://archive.org/details/isbn_9780881791327/page/80/mode/2up |quote=In typescript, a double hyphen (--) is often used for a long dash. Double hyphens in a typeset document are a sure sign that the type was set by a typist, not a typographer. A typographer will use an em dash, three-quarter em, or en dash, depending on context or personal style. The em dash is the nineteenth-century standard, still prescribed in many editorial style books, but the em dash is too long for use with the best text faces. Like the oversized space between sentences, it belongs to the padded and corseted aesthetic of Victorian typography.}}</ref> In the TeX typesetting languages, a single hyphen-minus (<code>-</code>) renders a hyphen, a single hyphen-minus in math mode (<code>$-$</code>) renders a minus sign, two hyphen-minuses (<code>--</code>) renders an en dash, and three hyphen-minuses (<code>---</code>) renders an em dash.

The hyphen-minus character is also often used when specifying [[command-line option]]s. The character is usually followed by one or more letters that indicate specific actions. Typically it is called a dash or switch in this context. Various implementations of the [[getopt]] function to parse command-line options additionally allow the use of two hyphen-minus characters, {{code|--}}, to specify long option names that are more descriptive than their single-letter equivalents. Another use of hyphens is that employed by programs written with [[Pipeline (Unix)|pipelining]] in mind: a single hyphen may be recognized [[wikt:in lieu|in lieu]] of a filename, with the hyphen then serving as an indicator that a [[standard streams|standard stream]], instead of a file, is to be worked with.

=== Soft and hard hyphens ===
{{Further|Soft hyphen}}

Although software ([[hyphenation algorithm]]s) can often automatically make decisions on when to hyphenate a word at a line break, it is also sometimes useful for the user to be able to insert cues for those decisions (which are dynamic in the online medium, given that text can be [[Reflowable document|reflowed]]). For this purpose, the concept of a [[soft hyphen]] (discretionary hyphen, optional hyphen) was introduced, allowing such manual specification of a place where a hyphenated break is ''allowed'' but not ''forced''. That is, it does not force a line break in an inconvenient place when the text is later reflowed.

Soft hyphens are inserted into the text at the positions where hyphenation ''may'' occur. It can be a tedious task to insert the soft hyphens by hand, and tools using hyphenation algorithms are available that do this automatically. Current modules{{which|date=February 2021}} of the [[Cascading Style Sheets]] (CSS) standard provide language-specific hyphenation dictionaries.

In contrast, a hyphen that is always displayed and printed is called a {{Anchor|hard hyphen}}"hard hyphen". This can be a Unicode hyphen, a hyphen-minus, or a nonbreaking hyphen (see [[#Nonbreaking hyphens|below]]). Confusingly, the term is sometimes limited to nonbreaking hyphens.{{cn|date=October 2022}}

=== Nonbreaking hyphens <span class="anchor" id="non-breaking hyphen"></span> <span class="anchor" id="nonbreaking hyphen"></span> <span class="anchor" id="no-break hyphen"></span>===
<!-- Section header used as link target in redirects -->

The [[word segmentation]] rules of most text systems consider a hyphen to be a [[word boundary (linguistics)|word boundary]] and a valid point at which to break a line when flowing text. This is not always desirable, it could lead to ambiguity (e.g. ''retreat'' and ''re‑treat'' would be indistinguishable with a line break after ''re''), it can split off an ending as in "''n''{{nbh}}th" (though ''n''<sup>th</sup> or "''n''th" could be used), and it is inappropriate in some languages other than English (e.g., a line break at the hyphen in [[Irish language|Irish]] {{lang|ga|an t‑athair}} or [[Romanian language|Romanian]] {{lang|ro|s‑a}} would be undesirable). The '''non-breaking hyphen''', '''nonbreaking hyphen''', or '''no-break hyphen''' looks identical to the regular hyphen, but word processors do not break words at it. The [[nonbreaking space]] exists for similar reasons.

==="Unicode hyphen" <span class="anchor" id="Unicode hyphen"></span> ===
Because the conventional ''hyphen-minus'' mark on keyboards is ambiguous (it can be interpreted{{snd}} sometimes unexpectedly{{snd}} as a hyphen or a minus, depending on context), in addition the [[Unicode consortium]] allocated [[codepoint]]s for an unambiguous minus and an unambiguous hyphen. The Unicode hyphen ({{unichar|2010|hyphen}}) is seldom used. Even the [[Unicode Standard]] uses U+002D instead of U+2010 in its text.<ref>{{cite web|last=Korpela|first=Jukka K.|title=Dashes and hyphens|date=December 2020|url=https://jkorpela.fi/dashes.html#usage|website=IT and Communication}}</ref> 

== Use in date notation ==
{{Further|Date format by country}}

Use of hyphens to delineate the parts of a written date (rather than the [[slash (punctuation)|slashes]] used conventionally in [[Anglophone]] countries) is specified in the [[international standard]] [[ISO 8601]]. Thus, for example, 1789-07-14 is the standard way of writing the date of [[Bastille Day]]. This standard has been transposed as European Standard EN 28601 and has been incorporated into various national typographic style guides (e.g., [[DIN]] 5008 in Germany). Now all official European Union (and many member state) documents use this style.  This is also the typical date format used in large parts of Europe and Asia, although sometimes with other separators than the hyphen.

This method has gained influence within North America, as most common computer [[file system]]s make the use of slashes in [[file name]]s difficult or impossible. [[MS-DOS]], [[OS/2]] and [[Windows]] use {{code|/}} to introduce and separate switches to [[shell (computing)|shell]] commands, and on both Windows and [[Unix-like]] systems slashes in a filename introduce subdirectories which may not be desirable. Besides encouraging use of dashes, the Y-M-D order and zero-padding of numbers less than 10 are also copied from ISO 8601 to make the filenames sort by date order.

== Unicode ==
{{Special characters|Unicode|section}}
Unicode has multiple hyphen characters:<ref name="PropList">{{cite web|url=https://www.unicode.org/Public/UCD/latest/ucd/PropList.txt|title=Unicode PropList.txt|date=2025-06-30|access-date=2025-09-23}}</ref>
* {{unichar|002D|HYPHEN-MINUS|nlink=hyphen-minus|html=}}, a character of multiple uses
* {{unichar|00AD|SOFT HYPHEN|nlink=soft hyphen|html=}}{{efn|The soft hyphen serves as an invisible marker that is used to specify a place in text where a hyphenated [[Line wrap and word wrap|line break]] is preferred should one be needed. This avoids forcing a line break in an inconvenient place, should the text be reflowed. It becomes visible only if [[Line wrap and word wrap|word wrapping]] occurs at the end of a line.}}
* {{unichar|2010|HYPHEN|html=}}
* {{unichar|2011|NON-BREAKING HYPHEN|html=}}
* {{unichar|2E5D|OBLIQUE HYPHEN}} for medieval texts<ref>{{cite web|title=L2/21-036 Proposal to add the Oblique Hyphen|url=https://www.unicode.org/L2/L2021/21036-n5152-oblique-hyphen.pdf|first1=Michael|last1=Everson|date=2021-01-12|access-date=2022-09-19}}</ref>

And in non-Latin scripts:<ref name="PropList" />
* {{unichar|058A|ARMENIAN HYPHEN}}
* {{unichar|05BE|HEBREW PUNCTUATION MAQAF}}
* {{unichar|1806|MONGOLIAN TODO SOFT HYPHEN}}
* {{unichar|1B60|BALINESE PAMENENG}} (used only as a line-breaking hyphen)
* {{unichar|2E17|DOUBLE OBLIQUE HYPHEN}} (used in ancient Near-Eastern linguistics and in [[blackletter]] typefaces)
* {{unichar|30FB|KATAKANA MIDDLE DOT}} (has the Unicode property of "Hyphen" despite its name)
* {{unichar|FE63|SMALL HYPHEN-MINUS}} (compatibility character for a small hyphen-minus, used in East Asian typography)
* {{unichar|FF0D|FULLWIDTH HYPHEN-MINUS}} (compatibility character for a wide hyphen-minus, used in East Asian typography)
* {{unichar|FF65|HALFWIDTH KATAKANA MIDDLE DOT}} (compatibility character for a wide katakana middle dot, has the Unicode property of "Hyphen" despite its name)

Unicode distinguishes the hyphen from the general [[interpunct]]. The characters below do not have the Unicode property of "Hyphen" despite their names:<ref name="PropList" />
* {{unichar|1400|CANADIAN SYLLABICS HYPHEN}}
* {{unichar|2027|HYPHENATION POINT}}
* {{unichar|2043|HYPHEN BULLET|html=}}
* {{unichar|2E1A|HYPHEN WITH DIAERESIS}}
* {{unichar|2E40|DOUBLE HYPHEN|nlink=double hyphen}}
* {{unichar|30A0|KATAKANA-HIRAGANA DOUBLE HYPHEN}}
* {{unichar|10EAD|YEZIDI HYPHENATION MARK|use=script|use2=Yezi}}
* {{unichar|10D6E|GARAY HYPHEN}}

(See [[interpunct]] and [[bullet (typography)]] for more round characters.)

== See also ==

* {{Annotated link |De-hyphenation}}
* {{Annotated link |Double hyphen}}
* {{Annotated link |French orthography#Hyphens|French orthography § Hyphens}}
* {{Annotated link |Hyphen War}}
* {{Annotated link |Greek hyphen}} ("Papyrological hyphen")
* {{Annotated link |Enhypen}}, whose name refers to the hyphen

== Notes ==
{{Notelist}}

== References ==
{{Reflist}}

== External links ==
{{Wiktionary}}
* [[wikt:Category:English terms spelled with -|Wiktionary list of English phrases spelled with a hyphen]]
* [http://www.economist.com/styleguide/introduction Economist Style Guide—Hyphens]
* [https://linguapress.com/grammar/points/hyphens.htm Using hyphens in English; rules and recommendations]
* Jukka Korpela, [https://jkorpela.fi/shy.html Soft hyphen (SHY)—a hard problem?] (See also his article on [https://jkorpela.fi/html/nobr.html word breaking, line breaks, and special characters (including hyphens) in HTML]).
* Markus Kuhn, [http://www.cl.cam.ac.uk/~mgk25/ucs/L2/03155r-kuhn-soft-hyphen.pdf Unicode interpretation of SOFT HYPHEN breaks ISO 8859-1 compatibility]. Unicode Technical Committee document L2/03-155R, June 2003.
* [https://web.archive.org/web/20080501023846/http://www.gpoaccess.gov/stylemanual/2000/chapter_txt-6.html United States Government Printing Office Style Manual 2000] 6. Compounding Rules]

{{Typography terms}}
{{navbox punctuation}}
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[[Category:Punctuation]]
[[Category:Punctuation of English]]