A term used in the classification of lip position in phonetics, referring to the visual appearance of the lips when they assume a rounded shape. Each of the vowel position on the cardinal vowel diagram has both a rounded and an unrounded form. Lip position is of particular phonological significance in the analysis of vowel and semi-vowel qualities. The opposition rounded/non-rounded has special status in Chomsky and Halle’s distinctive feature theory of phonology, where it handles variations in place of articulation, specifying lip position. ‘Rounded’ sounds are defined articulatorily, as those produced with a narrowing of the lips, as in [w], [u], etc. Its opposite is non-rounded, referring to sounds produced without any such narrowing, as in English front vowels.


语音学用来给唇位分类,指双唇呈圆唇的外观。基本元音图上每个元音位置都有圆唇和不圆唇两个形式。事实上在分析元音和半元音的音质时,唇位在音系学上有特别重要的意义。圆唇/非圆唇对立在乔姆斯基和哈勒的音系学区别特征理论中有特殊地位,用来描写发音部位的变异(腔特征),具体是唇位变化。“圆唇”音从发音上定义为双唇的间隙收窄,如[w] 、[u]等。相对立的是非圆唇音,指双唇不这么收窄发出的音,如英语的前元音。