rat on
Inform the authorities
To rat on someone is to inform against them, especially to authorities: He ratted on his accomplices to get a lighter sentence.
The phrase carries strong connotations of betrayal and disloyalty—rats abandon sinking ships, and a rat abandons loyalty to save himself.
Less commonly, to rat on a promise or agreement is to break it.
One who tells authorities
- informantOne who provides intelligence
- finkContemptible informer
- tattletaleOne who informs on others
- whistleblowerInsider who reports misconduct
stool pigeon · squealer · narc · grass · canary · tipster · deep throat · leaker
One who tells authorities
- tattleReveal another's wrongdoing
- squealShrill, piercing cry
- reportFormal written findings
- exposeMake known publicly
divulge · reveal · disclose · leak · testify · confess · blab · tip off
Violate a trust
- backstabBetray someone's trust
- double-crossTreacherous deception of partner
- sell outBetray one's values
- turn againstBecome hostile toward
stab in the back · two-time · deceive · treachery · perfidy · disloyalty · unfaithful · forsake
snitch
One who tells authorities
- informantOne who provides intelligence
- finkContemptible informer
- tattletaleOne who informs on others
whistleblower · stool pigeon · squealer · narc · grass · canary · tipster · deep throat · leaker · mole
snitch
One who tells authorities
expose · divulge · reveal · disclose · leak · testify · confess · blab · tip off · turn in
betray
Violate a trust
- backstabBetray someone's trust
- double-crossTreacherous deception of partner
- sell outBetray one's values
turn against · stab in the back · two-time · deceive · treachery · perfidy · disloyalty · unfaithful · forsake · abandon
rat onstonewall
Refuse to cooperate
clam up · plead the fifth · say nothing · cover up · conceal
rat oncover up
Conceal misdeeds or errors
keep mum · keep secret · hush up · conceal · say nothing
on, rat, rats, ratty, ratted, ratting, ratter, rathole, ratlike