[dif-thawng, -thong, dip-] 
| 1. | 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. |
| 2. | (not in technical use)
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| 3. | to diphthongize. |
[dif-thawng-guhl, -thong-, dip-] , diph⋅thon⋅gic, diph⋅thon⋅gous, adjective | diph·thong (dĭf'thông', -thŏng', dĭp'-) n. A complex speech sound or glide that begins with one vowel and gradually changes to another vowel within the same syllable, as (oi) in boil or (ī) in fine. [Middle English diptonge, from Old French diptongue, from Late Latin diphthongus, from Greek diphthongos : di-, two; see di-1 + phthongos, sound.] diph·thon'gal adj. |
diphthong
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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