What is Diphthongs?

Diphthongs definition and meaning on Dictionary terms:
Phonetics. 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.
(not in technical use) a digraph, as the ea of meat. a ligature, as A|.

verb (used with or without object)
to diphthongize.


reference: https://www.dictionary.com/browse/diphthongs