1. rude slang To exert a significant amount of energy or work very hard to do, accomplish, or complete something. I've been busting my ass all night long to get this presentation ready for tomorrow's meeting. She's going to have to bust her ass if she wants a place on the varsity team.

2. rude slang To harass, nag, or upbraid one to do, accomplish, or complete something. The boss is busting everyone's ass to get the project ready by next week. Quit busting my ass! I'll get it done eventually!

3. rude slang To defeat one decisively. We weren't prepared for the game, and the other team busted our asses.

4. rude slang To physically attack one; to beat one up. I'll bust your ass if I ever see you talking to my girlfriend again.

5. rude slang To tease one; to give one a hard time. Aw, come on, dude, I was just busting your ass. No need to get upset about it.