The mid back rounded vowel is a type of vowel sound, used in some spoken languages. While there is no dedicated symbol in the International Phonetic Alphabet that represents the exact mid back rounded vowel between close-mid [o] and open-mid [ɔ], it is normally written 〈o〉. If precision is desired, diacritics may be used, such as 〈o̞〉 or 〈ɔ̝〉, the former being more common. A non-IPA letter 〈ⱺ〉 is also found.
Note that just because a language has only one non-close non-open back vowel, it still may not be a cardinal mid vowel. The Sulawesian language Tukang Besi, for example, has a close-mid [o], whereas the Moluccan language Taba has an open-mid [ɔ]; in neither language does this contrast with another open close-mid vowel. The Kensiu language spoken in Malaysia and Thailand is highly unusual in that it contrasts true-mid vowels with close-mid and open-mid vowels without differences in other parameters such as backness or roundedness.
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