The open front unrounded vowel, or low front unrounded vowel, is a type of vowel sound, used in many spoken languages. According to the official standards of the International Phonetic Association, the symbol in the International Phonetic Alphabet that represents this sound is ⟨a⟩.
In practice, however, it is very common to approximate this sound with ⟨æ⟩ (officially a near-open (near-low) front unrounded vowel), and to use ⟨a⟩ as an open (low) central unrounded vowel. This is the normal practice, for example, in the historical study of the English language. The loss of separate symbols for open and near-open front vowels is usually considered unproblematic, because the perceptual difference between the two is quite small, and very few languages contrast the two. See open central unrounded vowel for more information. If one needs to specify that the vowel is front, they can use symbols like [a̟] ([a] with "advanced" diactric), or [æ̞] (lowered [æ]), with the latter being more common.
The Limburgish dialect of Hamont has been reported to contrast open front, central and back unrounded vowels,[1] which is extremely unusual.
The IPA prefers terms "close" and "open" for vowels, and the name of the article follows this. However, a large number of linguists,[who?] perhaps a majority, prefer the terms "high" and "low".
