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Synonyms

mouth off

British  

verb

  1. informal to give an opinion or speak emotionally, often without much care or consideration

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
mouth off Idioms  

  1. Complain or express one's opinions loudly and indiscreetly, as in She was always mouthing off about the other members . [ Slang ; 1960s]

  2. Speak impudently, talk back, as in He got in trouble by mouthing off to his teacher . [ Slang ; 1960s]

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

Sir Keir Starmer isn't a man to shoot his mouth off in public.

From BBC • Jan. 19, 2026

At 56, Imperioli is no longer the scrawny kid who dared mouth off to Joe Pesci’s volcanic gangster in “Goodfellas.”

From Los Angeles Times • Nov. 21, 2022

"She's trying to defend her daughter, why doesn't she stop shouting her mouth off and take ownership of how she raised her daughter," Imbriale told Fox News Digital Tuesday.

From Fox News • Jan. 11, 2022

When a teenage Thomas Bryant would grow too aggressive, commit too many fouls or mouth off at a referee during his college days at Indiana, Hoosiers Coach Tom Crean always resorted to eye contact.

From Washington Post • Jan. 5, 2021

“Since when don’t you turn your mouth off when I’m eating?”

From "The Milagro Beanfield War" by John Nichols

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.