A single vowel articulated without change in quality throughout the course of a syllable, as the vowel of English bed.
Two written vowels representing a single sound, as oa in boat.
A simple vowel sound during the utterance of which the vocal organs remain in a relatively unchanging position, as (ä), (), or (i)
A vowel (in the sense of a sound rather than a letter of the alphabet) that has the same sound throughout its pronunciation, such as the short vowels in "pap", "pep", "pip", "pop" and "pup", as opposed to a diphthong (eg, /aÉª/, the vowel in "pipe") or a triphthong (eg, /aÉªÉ™/, the sound in the non-rhotic pronunciation of "pyre").
Origin of monophthong
From Ancient Greek Î¼Î¿Î½ÏŒÏ†Î¸Î¿Î³Î³Î¿Ï‚ (monophthongos), from Î¼ÏŒÎ½Î¿Ï‚ (monos, “single") + Ï†Î¸ÏŒÎ³Î³Î¿Ï‚ (phthongos, “sound").