n. 增音, 插音

[ noun ]
the insertion of a vowel or consonant into a word to make its pronunciation easier
<noun.communication>
the insertion of a vowel in the plural of the word `bush' is epenthesis

Epenthesis \E*pen"the*sis\, n.; pl. {Epentheses}. [L., fr. Gr.
?; 'epi` + ? to put or set in.] (Gram.)
The insertion of a letter or a sound in the body of a word;
as, the b in ``nimble'' from AS. n[=e]mol.