|diphthong (ˈdɪfθɒŋ, ˈdɪp-)|
|1.||a vowel sound, occupying a single syllable, during the articulation of which the tongue moves from one position to another, causing a continual change in vowel quality, as in the pronunciation of a in English late, during which the tongue moves from the position of (e) towards ()|
|2.||a digraph or ligature representing a composite vowel such as this, as ae in Caesar|
|[C15: from Late Latin diphthongus, from Greek diphthongos, from |
in phonetics, a gliding vowel in the articulation of which there is a continuous transition from one position to another. Diphthongs are to be contrasted in this respect with so-called pure vowels-i.e., unchanging, or steady state, vowels. Though they are single speech sounds, diphthongs are usually represented, in a phonetic transcription of speech, by means of a pair of characters indicating the initial and final configurations of the vocal tract. Many of the vowel sounds in most dialects of English are diphthongs: e.g., the vowels of "out" and "ice," represented as [au] and [ai], respectively.
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