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 ,
Silent letter Silent letter In an alphabetic writing system, a silent letter is a letter that, in a particular word, does not correspond to any sound in the word's pronunciation. Phonetic transcriptions that better depict pronunciation and which note changes due to grammar and proximity of other words require a symbol to show that the letter is mute. Handwritten notes use a circle with a line through it and the sound is called "zero"; It resembles the symbol for the "empty set", but must not be confused with the Danish and Norwegian letter Ø. In printed or computer's graphic presentation, the symbol