epenthesis of a vowel – insertion of a vowel. Including, the center ‘-a-’ in thataway, or utilization of infixes -i- and -o- in coining English words on classical roots.
In phonetics, the involuntary utterance of an auxiliary vowel, especially before r, l, m, and n, in some opportunities, as with lucre, ready, chasm, etc.
How would you define anaptyxis?