The open front unrounded vowel, or low front unrounded vowel,<ref>Template:Vowel terminology</ref> is a type of vowel sound used in some spoken languages. It is one of the eight primary cardinal vowels, not directly intended to correspond to a vowel sound of a specific language but rather to serve as a fundamental reference point in a phonetic measuring system.<ref>John Coleman: Cardinal vowels</ref>
The symbol in the International Phonetic Alphabet (IPA) that represents this sound is Template:Angbr IPA, a double-story lowercase a. In the IPA vowel chart it is positioned at the lower-left corner. However, the accuracy of the quadrilateral vowel chart is disputed, and the sound has been analyzed acoustically as extra-open at a position where the front/back distinction has lost its significance. There are also differing interpretations of the exact quality of the vowel: the classic sound recording of Template:IPA by Daniel Jones is slightly more front but not quite as open as that by John Wells.<ref>Geoff Lindsey (2013) The vowel space, Speech Talk</ref>
Template:Open vowelTemplate:Front vowel This subsumes central open (central low) vowels because the tongue does not have as much flexibility in positioning as it does in the mid and close (high) vowels; the difference between an open front vowel and an open back vowel is similar to the difference between a close front and a close central vowel, or a close central and a close back vowel.
Template:Unrounded vowel
Many languages have some form of an unrounded open vowel. For languages that have only a single open vowel, the symbol for this vowel Template:Angbr may be used because it is the only open vowel whose symbol is part of the basic Latin alphabet. Whenever marked as such, the vowel is closer to a central Template:IPA than to a front Template:IPA. However, there may not actually be much of a difference. (See Vowel#Acoustics.)
CaliforniaTemplate:Sfnp<ref name="thomas308">Template:Harvcoltxt: A few younger speakers from, e.g., Texas, who show the Template:Sc2/Template:Sc2 merger have Template:Sc2 shifted toward Template:IPA, but this retraction is not yet as common as in some non-Southern regions (e.g., California and Canada), though it is increasing in parts of the Midwest on the margins of the South (e.g., central Ohio).</ref>
