Rounded vowel

In phonetics, vowel roundedness refers to the amount of rounding in the lips during the articulation of a vowel. It is labialization of a vowel. When pronouncing a rounded vowel, the lips form a circular opening, whereas unrounded vowels (also called spread vowels) are pronounced with the lips relaxed. In most languages, front vowels tend to be unrounded, whereas back vowels tend to be rounded. But some languages, such as French and German, distinguish rounded and unrounded front vowels of the same height, whereas Vietnamese distinguishes rounded and unrounded back vowels of the same height. Alekano has only unrounded vowels.