grass on
In real, traceable use. Part of the curated seed collection; community review is coming.
Meaning · English
To betray by informing on.
Register: slang
Examples
What I was pissed off about, though, was him telling everyone that he'd only grassed on me because I'd grassed on him first, which was a total lie.
Usage example from English Wiktionary (CC BY-SA 4.0, retrieved 2026-07-30)
Sources & notes
Adapted from English Wiktionary (CC BY-SA 4.0, retrieved 2026-07-30 via kaikki.org).
Common questions
What does “grass on” mean?
To betray by informing on.
Is “grass on” formal or informal?
grass on is generally slang.