tells on
Reports to authorities
To tell on someone is to report their wrongdoing to an authority—a parent, teacher, or boss: If you don't stop, I'm going to tell on you.
The phrase carries childish connotations; adults more often say report or inform.
Separately, something tells on a person when it reveals hidden information or takes a visible toll: The stress was telling on her face.
- telltaleRevealing indicator
- confessesAcknowledges wrongdoing openly
- implicatesSuggests connection to wrongdoing
- incriminatesShows evidence of guilt
- snitchesThose who betray confidences
drops a dime · informs · blows the whistle · whistleblows · tattles · spills the beans · finger · reveals · tarnishes · exposes · gives away · damages · betrays · leaks · denounces · undermines · gossips · divulges