epenthesis
noun
epen·the·sis i-ˈpen(t)-thə-səs 
e-
plural epentheses i-ˈpen(t)-thə-ˌsēz
e-
: the insertion or development of a sound or letter in the body of a word (such as \\ə\\ in \\ˈa-thə-ˌlēt\\ athlete)
epenthetic
ˌe-pən-ˈthe-tik
adjective 
Did you know?
If you say film as "FIL-um," with two syllables, you've committed epenthesis. It isn't a punishable offense-in fact, it's not an offense at all. It is simply a natural way to break up an awkward cluster of consonants. It's easier for some people to say film as two syllables instead of one, just as it's easier for some to insert a "b" sound into cummerbund, pronouncing that word as "CUM-ber-bund."
Word History
Etymology
Late Latin, from Greek, from epentithenai to insert a letter, from epi- + entithenai to put in, from en- + tithenai to put — more at do
First Known Use
1543, in the meaning defined above