Used to indicate that the person telling them should have told the speaker earlier, typically with annoyance.

Alternative form of tell its own tale.

I do not believe you; you are joking.

Alternative form of dead men tell no tales

Alternative form of you can't judge a book by its cover

A sarcastic response to when someone is told something obvious

(informal, vulgar) To tell someone an obvious lie.

Full name of the U.S. Military's "don't ask, don't tell" policy concerning the service of homosexuals in the military as defined in 10 USC § 654.