mouth off
verb
mouthed off; mouthing off; mouths off
informal
: to talk in a loud, unpleasant, or rude way
He got in trouble again for mouthing off to his teacher.
She's always mouthing off about how much better she could run the company herself.
Cite this Entry
“Mouth off.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/mouth%20off. Accessed 6 Mar. 2026.
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