laugh your head off

US /læf jʊər hɛd ɔf/
UK /læf jʊər hɛd ɔf/
"laugh your head off" picture
1.

大笑いする, 腹を抱えて笑う

to laugh very loudly and for a long time

:
The comedian was so funny, we were all laughing our heads off.
そのコメディアンはとても面白くて、私たちはみんな大笑いした
I told him a joke and he started to laugh his head off.
彼に冗談を言ったら、彼は大笑いし始めた