watch (one's) tongue(redirected from watch their tongues)
watch (one's) tongue
To be very mindful or cautious about what one says; to keep a check on one's language or control what one says. You'd better watch your tongue around these parts, mister, or you'll find yourself on the wrong end of someone's fist! After being threatened with expulsion for my vulgar remarks in class, I knew had to watch my tongue for the rest of the semester.
Farlex Dictionary of Idioms. © 2015 Farlex, Inc, all rights reserved.
Watch your tongue!verb
See also: watch
McGraw-Hill's Dictionary of American Slang and Colloquial Expressions Copyright © 2006 by The McGraw-Hill Companies, Inc. All rights reserved.