What does “laisse tomber” mean in French?

Laisse tomber is literally “let it fall,” and it does the work of “forget it” or “never mind.” It waves a subject away (laisse tomber, c’est pas grave), turns down an offer of help, or tells someone to give up on something altogether: laisse tomber la cuisine is “give up on cooking.” It is informal, and tone decides everything — the same two words can be kind or cutting.

Pointed at a person, the phrase keeps the falling image and turns cold: il m’a laissé tomber is “he let me down,” dropped me when it mattered. That is the same verb pair as laisser + infinitive elsewhere in French — laisser passer, laisser faire — where laisser means allowing something to happen rather than making it happen.