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a big mouth

1. A tendency or habit of speaking incessantly and indiscreetly, especially about sensitive or secret information. If I'd known you had such a big mouth, I'd have never shared my secret with you! God you've got a big mouth! Don't you ever stop talking about other people's business? Of course Bobby let it slip that there would be a surprise party for her birthday—that kid's got a big mouth.
2. A person who talks in such a manner. I can't stand Terry's new husband, he is such a big mouth! Now I'm in trouble, thanks to you being a big mouth and blabbing all about how I got home past curfew last night! We would have gotten away with the plan if she hadn't been such a big mouth!
See also: big, mouth

have a big mouth

To have a tendency or habit of speaking incessantly, indiscreetly, and/or in a noisy, boorish manner. I can't stand Terry's new husband, he has such a big mouth! It's like no one else gets a chance to speak when he's here. If I'd known you had such a big mouth, I'd have never shared my secret with you!
See also: big, have, mouth
Farlex Dictionary of Idioms. © 2022 Farlex, Inc, all rights reserved.

have a big mouth

to be a gossiper; to be a person who tells secrets. Mary has a big mouth. She told Bob what I was getting him for his birthday. You shouldn't say things like that about people all the time. Everyone will say you have a big mouth.
See also: big, have, mouth
McGraw-Hill Dictionary of American Idioms and Phrasal Verbs. © 2002 by The McGraw-Hill Companies, Inc.

have a big mouth

tv. to speak loudly and openly in public; to tell secrets. (Have got can replace have.) He has a big mouth. Don’t tell him anything you don’t want everybody else to know.
See also: big, have, mouth
McGraw-Hill's Dictionary of American Slang and Colloquial Expressions Copyright © 2006 by The McGraw-Hill Companies, Inc. All rights reserved.
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References in periodicals archive ?
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