Epenthesis of a vowel – insertion of a vowel. For example, the middle ‘-a-’ in thataway, or use of infixes -i- and -o- in coining English words on classical roots.(noun)
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Use "anaptyxis" in a sentence
"I might also be interested to find out that vowel insertion is widespread enough in the world's languages to have a name, epenthesis also called anaptyxis."
"The extra vowel use has a word for itself, anaptyxis."