open (one's) mouth

(redirected from opened their mouths)

open (one's) mouth

To say something, especially that which is indiscreet, boorish, or meant to be a secret. Why did you have to open your mouth about my crush on Tommy? Why couldn't you just keep it between us? You've got to make sure that he never opens his mouth about what went on here today.
See also: mouth, open
References in classic literature ?
I watched very carefully as he moved about among the Frogs; but I could not see that any of them opened their mouths to be fed-- except one very young one, and I'm nearly sure it did it accidentally, in yawning.
To impale prey with these impressive weapons, the famous sabretoothed cats must have opened their mouths wider than any modern big cat, but it was unclear if their jaw muscles were strong enough to do it.
NOW that Jack Straw and Tony Blair have opened their mouths about veils it seems everyone wants to have a go at us Muslims.
They spread their arms and opened their mouths in a silent cry.