Piss (oneself) laughing British slang rude
If one pisses himself/herself laughing, it means that he/ she laughs in an uncontrollable or crazy way.
We can't stop pissing ourselves laughing throughout of the film.
We are so lucky to have a hilarious teacher. Yesterday, we were pissing ourselves laughing during the lesson.
The verb “piss" should be conjugated according to its tense.
Go to bed
I feel so sleepy, so I want to hit the hay.