0 to secretly tell someone in authority, especially a teacher, that someone else has done something bad, often in order to cause trouble:
Did you tattle on us to the teacher?
No one is safe from being tattled on.
I think the worst use of the blind carbon copy is to rat out or tattle on a coworker.
When the son's manager finally had the courage to tattle to the boss, he fired his own son.
There's an implicit rank-pulling or tattling involved when you add an acc; bringing in someone else is no way to e-behave.
While no one wants to feel like they're "tattling" on a friend, there are times when it's appropriate to bring in another party.
Young children certainly tattle, but do they similarly manage reputations among peers through prosocial gossip?
She was such a tattle-tale.
They tattle when he opens the refrigerator.