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Synonyms

run off at the mouth

Idioms  

  1. Talk incessantly, babble, as in Wilbur is always running off at the mouth about his investments. This idiom transfers a flow of water to an unending flow of words. [Slang; c. 1900]

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.

And we can also be fairly certain that both athletes will continue to run off at the mouth before they run on the track.

From Los Angeles Times • Feb. 14, 2025

If you've ever met KT, you know he's not one to run off at the mouth with some excessive filler.

From Time Magazine Archive

Even with methodical training they were inclined to run off at the mouth, make unnecessary displays of themselves, unconsciously slip in the tiniest flourish that could scare off a nervous contact.

From "Native Speaker" by Chang-rae Lee

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.