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 ,
Thematic vowel Thematic vowel In Indo-European studies, a thematic vowel or theme vowel is the vowel or from ablaut placed before the ending of a Proto-Indo-European (PIE) word. Nouns, adjectives, and verbs in the Indo-European languages with this vowel are thematic, and those without it are athematic. Used more generally, a thematic vowel is any vowel found at the end of the stem of a word. PIE verbs and nominals (nouns and adjectives) consist of three parts: The thematic vowel, if present, occurs at the end of the suffix (which may include other vowels or consonants) and before the ending: Athematic forms,