Definition
To work hard, especially when trying to achieve a goal.
To fart.
Also Said As
- bust one's ass
How People Actually Use It
To bust ass is to fart. BUT if used with a possesive, it means to work hard. Also often used with a possessive and immediately followed by an infinitive
"I just busted ass and it smells real bad. You better be busting your ass if you want to finish the job on schedule. I was busting my ass to finish my homework on time."
Source: Urban Dictionary