Dictionary
diph•thong
Pronunciation: (dif'thông, -thong, dip'-), [key]—
n.
1. Phonet.an unsegmentable, gliding speech sound varying continuously in phonetic quality but held to be a single sound or phoneme and identified by its apparent beginning and ending sound, as the
oi-sound of
toy or
boil.
2. (not in technical use)
a. a digraph, as the
ea of
meat.
b. a ligature, as æ.
—
v.t., v.i.
to diphthongize.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.