A monophthong (Greek μονόφθογγος, "monophthongos" = single note)'s a "pure" vowel sound, one whose articulation at both beginning and end's relatively fixed, and which doesn't glide up or down towards a new position of articulation; compare diphthong. In the English language, there're in practice relatively few monophthongs. The position, beginnings, and endings of vowel articulation are perhaps the chief distinguishing feature among the v… (
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