元音圓唇度

Also known as vowel labialization, labialization, labialisation, vowel labialisation

In phonetics, vowel roundedness is the rounding of the lips, or lack thereof, during the articulation of a vowel. It is the degree and kind of labialization of a vowel. In the International Phonetic Alphabet vowel chart, rounded vowels are the ones that appear on the right in each bulleted pair of letters, and the corresponding unrounded vowels are the ones on the left, with (when central) and the unpaired vowels and being neutral or unspecified. In most dialects of English, the vowel with the greatest degree of rounding is , as in the word too, though some languages have significantly greater