unround

/ʌnˈraʊnd/
verb
  1. To change the shape of the lips from a rounded to a spread or neutral position when pronouncing a sound.
    • When learning French, she had to practice not unrounding certain vowels.
    • In some dialects, speakers unround the vowel in 'cot' so it sounds like 'cat'.
    • The linguist asked the student to unround their lips for the 'ee' sound.
Antonyms
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