Екі дауысты дыбыстың бірігуі

Combination of two adjacent vowel sounds

A diphthong ('/d//ɪ//f//θ//ɒ//ŋ//, /'/d//ɪ//p// / DIFthong, DIP ; from Ancient Greek δίφθογγος (díphthongos) 'two sounds', from δίς (dís) 'twice'), also known as a gliding vowel, is a combination of two adjacent vowel sounds within the same syllable. Technically, a diphthong is a vowel with two different targets: that is, the tongue (and/or other parts of the speech apparatus) moves during the pronunciation of the vowel. In most varieties of English, the phrase "no highway cowboy" (/n//oʊ// /'/h//aɪ//w//eɪ// /'/k//aʊ//b//ɔɪ/ noh HYway KOWboy) has five distinct diphthongs, one in every syllable. Diphthongs contrast with monophthongs, where the tongue or other speech organs do not move and the syllable contains only a single vowel sound. For instance, in English, the word ah is spoken as a monophthong (/ɑː/), while the word ow is spoken as a diphthong in most varieties (/aʊ/). Where two adjacent vowel sounds occur in different syllables (e. g. in the English word re elect) the result is described as hiatus, not as a diphthong. Diphthongs often form when separate vowels are run together in rapid speech during a conversation. However, there are also unitary diphthongs, as in the English examples above, which are heard by listeners as single vowel sounds (phonemes).

Falling (or descending) diphthongs start with a vowel quality of higher prominence (higher pitch or volume) and end in a semivowel with less prominence, like in eye, while rising (or ascending) diphthongs begin with a less prominent semivowel and end with a more prominent full vowel, similar to the in yard. (Sometimes, however, the terms "falling" and "rising" are used, instead, to refer to vowel height, i. e. as synonyms of the terms "closing" and "opening". See below.) The less prominent component in the diphthong may also be transcribed as an approximant, thus in eye and in yard. However, when the diphthong is analysed as a single phoneme, both elements are often transcribed with vowel symbols (, ). Semivowels and approximants are not equivalent in all treatments, and in the English and Italian languages, among others, many phoneticians do not consider rising combinations to be diphthongs, but rather sequences of approximant and vowel. There are many languages (such as Romanian) that contrast one or more rising diphthongs with similar sequences of a glide and a vowel in their phonetic inventory (see semivowel for examples).