look up any word, like spook:
 
1.
When a person wants to say something that may be offensive or hurtful to someone, so instead says nothing.

Opposite of speaking your mind.
She asked me if I liked her play. I just bit my tongue and nodded.

If somebody asks if you think there is something wrong with them, it is best to bite your tongue and say nothing.
by liquidtenmillion November 26, 2006
 
2.
what you say to someone who says something that you disapprove of
Sammy: "say Sally, isn't your 40th birthday just around the corner?"

Sally: (with icy look in her eyes) ".....bite your tongue old man!"
by polo January 25, 2006
 
3.
A response to something you don't want to hear.
Andy: But you hate me. :
Cait: Bite your tongue! I do not.
by J <3 April 19, 2006