Noun
The insertion of a letter or a sound in the body of a word; as, the b in "nimble" from AS. n/mol.
Source: Webster's dictionarythe insertion of a vowel in the plural of the word `bush' is epenthesis Source: Internet
Apocope There was a tendency to eliminate final consonants in Vulgar Latin, either by dropping them ( apocope ) or adding a vowel after them ( epenthesis ). Source: Internet
Some scholars reserve the term epenthesis for "intrusive" vowels and use excrescence for intrusive consonants. Source: Internet