Close-mid central unrounded vowel Close-mid central unrounded vowel 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 . This is a mirrored letter e, and should not be confused with the schwa , which is a turned e. It was added to the IPA in 1993; before that, this vowel was transcribed (Latin small letter e with umlaut, not Cyrillic small letter yo). Certain older sources transcribe this vowel . The letter may be used with a lowering diacritic ,
Vowel harmony (usually consonant segments). In other words, "harmony" refers to the assimilation of sounds that are "not" adjacent to each other. For example, a vowel at the beginning of a word can trigger assimilation in a vowel at the end of a word. The assimilation occurs across the entire word in many languages. This is represented schematically in the following diagram: In the diagram above, the V (type-a vowel) causes the following V (type-b vowel) to assimilate and become the same type of vowel (and thus they become, metaphorically, "in harmony"). The vowel that causes the vowel assimilation is frequently termed