The close-mid central unrounded vowel, or high-mid central unrounded vowel, is a type of vowel sound used in some spoken languages. The symbol in the International Phonetic Alphabet that represents this sound is ⟨ɘ⟩. This is a mirrored letter e and should not be confused with the schwa⟨ə⟩, which is a turned e. It was added to the IPA in 1993; before that, this vowel was transcribed ⟨ë⟩ (Latin small letter e with diaresis, not Cyrillic small letter yo). Certain older sources transcribe this vowel ⟨ɤ̈⟩.
Conversely, ⟨ə⟩, the symbol for the mid central vowel may be used with a raising diacritic ⟨ə̝⟩ to denote the close-mid central unrounded vowel, although that is more accurately written with an additional unrounding diacritic ⟨ə̝͑⟩ to explicitly denote the lack of rounding (the canonical value of IPA ⟨ə⟩ is undefined for rounding).
Chirkova, Katia; Chen, Yiya (2013a), "Lizu", Journal of the International Phonetic Association, 43 (1): 75–86, doi:10.1017/S0025100312000242
Chirkova, Katia; Chen, Yiya (2013b), "Xumi, Part 1: Lower Xumi, the Variety of the Lower and Middle Reaches of the Shuiluo River", Journal of the International Phonetic Association, 43 (3): 363–379, doi:10.1017/S0025100313000157
Chirkova, Katia; Chen, Yiya; Kocjančič Antolík, Tanja (2013), "Xumi, Part 2: Upper Xumi, the Variety of the Upper Reaches of the Shuiluo River", Journal of the International Phonetic Association, 43 (3): 381–396, doi:10.1017/S0025100313000169
Iivonen, Antti; Harnud, Huhe (2005), "Acoustical comparison of the monophthong systems in Finnish, Mongolian and Udmurt", Journal of the International Phonetic Association, 35 (1): 59–71, doi:10.1017/S002510030500191X, S2CID145733117