tattle on (one)

tattle on (one)

Especially of children, to inform an authority figure of one's bad behavior. I can't believe you tattled on me like that to mom and dad—I'm never telling you anything ever again! I know you think you're trying to do the right thing, but you're going to have a hard time making friends if you tattle on your classmates for every little thing they do wrong.
See also: on, tattle
Farlex Dictionary of Idioms.

tattle on

v.
To inform that someone has misbehaved: My brother tattled on me for spilling the glue.
See also: on, tattle
The American Heritage® Dictionary of Phrasal Verbs.
See also:
  • tattle on
  • going to tell
  • tattle
  • going to tattle
  • inform on
  • inform on (one)
  • grass on (one)
  • grasse
  • inform against (one)
  • give notice