1. tell tales - Noun
2. tell tales - Verb
(idiomatic) To lie, to be making false claims.
Don't listen to him; he's telling tales.
(UK) To report someone in authority for a wrongdoing.
tell tales
plural of tell tale
I first began to tell tales to delight the world and make it wiser... Karen Blixen
To get a child's trust - you may know or not - is a very hard thing to do. They're so used to not believing adults - because adults tell tales and lies all the time. Maurice Sendak
She speaketh as she would créepe into your bosome. And when the meale mouth hath woon the bottome of your stomake, than will the pickthanke it tell To your most enmies, you to bye and fell. To tell tales out of schoole, that is hir great lust. Looke what she knowth, blab it wist, out it must. John Heywood
Some who just tell tales of themselves. Italian Proverb
To tell tales out of school. Japanese Proverb
Never tell tales out of school. Latin Proverb