Triphthong

In phonetics, a triphthong (UK: , US: ) (from Greekτρίφθογγοςtriphthongos, lit.'with three sounds' or 'with three tones') is a monosyllabicvowel combination involving a quick but smooth movement of the articulator from one vowel quality to another that passes over a third. While "pure" vowels, or monophthongs, are said to have one target articulator position, diphthongs have two and triphthongs three.

Triphthongs are not to be confused with disyllabic sequences of a diphthong followed by a monophthong, as in German Feuer 'fire', where the final vowel is longer than those found in triphthongs.