The close-mid front 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 e, and the equivalent X-SAMPA symbol is e.
Its vowel backness is front, which means the tongue is positioned as far forward as possible in the mouth without creating a constriction that would be classified as a consonant.
Many languages, Spanish, Japanese, Korean, Greek and Turkish, have a mid front unrounded vowel that is clearly distinct to speakers from both the close-mid and open-mid vowels. A number of dialects of such as English also have such a mid-front vowel. However, since no language is known to distinguish all three, there is no separate IPA symbol for the mid vowel, and [e] is generally used. If precision is desired, the lowering diacritic can be used: [e̞].
Although many languages have only one non-close, non-open front vowel, there is no predisposition for it being mid. Igbo, for example, has a close-mid [e], whereas Bulgarian has an open-mid [ɛ] even though these languages don't contrast said vowels with another front mid vowel.
Occurrence
In the following transcriptions, the lowering diacritic has been omitted for the sake of simplicity.
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Cruz-Ferreira, Madalena (1995), "European Portuguese", Journal of the International Phonetic Association25 (2): 90-94
Fougeron, Cecile & Caroline L Smith (1993), "Illustrations of the IPA:French", Journal of the International Phonetic Association23 (2): 73-76
Jones, Daniel & Ward Dennis (1969), The Phonetics of Russian, Cambridge University Press
Martínez-Celdrán, Eugenio; Ana Ma. Fernández-Planas & Josefina Carrera-Sabaté (2003), "Castilian Spanish", Journal of the International Phonetic Association33 (2): 255-259
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Shosted, Ryan K. & Chikovani Vakhtang (2006), "Standard Georgian", Journal of the International Phonetic Association36 (2): 255-264