Meaning of “grass on sb” in the English Dictionary

british dictionary

"grass on sb" in British English

See all translations

grass on sb

UK slang
phrasal verb with grass uk /ɡrɑːs/ us /ɡræs/ verb

If a person grasses on someone else, they tell the police or someone in authority about something bad that that person has done:

Dan grassed on them to the local police.

(Definition of “grass on sb” from the Cambridge Advanced Learner’s Dictionary & Thesaurus © Cambridge University Press)