Refering to an after affect of a substance, usually a drugs or alchol, that leave you in an altered, but sublime, state.
Girl 1: Girl last night, I has some green and was on my ass, I was so fucked up. That shit was some fire. I'm tryna get some yeah again, tonight.
by PG Dee (yeah that's it) November 30, 2005
being super drunk/fucked up from weed/alc etc, but at a relaxed state
“I was on my ass after 2 bong hits and an edible
by aidenthetank December 9, 2020
being super fucked up from a drug of some sort, but being at a relaxed state
“i was on my ass when i took 2 bong hits and an edible
by aidenthetank December 9, 2020
When someone says something and you think it’s a lie. / You don’t believe in what they’re saying
Person 1: Me and name are in a relationship

Person 2: Relationship my ass
Product of an owl and a bungee cord. (See Kung Pow for reference)
What do you get when you cross an owl with a bungee cord... MY ASS!
by Anonymous June 25, 2003
The best thing you can say to someone when they offend you
Guy 1: you r so ugly
Guy 2: ugly my ass
by Your friend next door down March 19, 2019