Definition of open one's mouth in English:

open one's mouth

  • informal Say something: sorry, I’ll never open my mouth about you again
    More example sentences
    • I try to assume less before opening my mouth or offering information.
    • You didn't even manage to get accurate information before you opened your mouth.
    • After spending a great deal of the 1990s making speeches on education, I took a vow never to open my mouth on the subject again, at least in public.
See parent entry: mouth

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