We found 2 dictionaries that define the word bust one's butt:

General (1 matching dictionary)

1. bust one's butt: Wiktionary

Slang (1 matching dictionary)

2. American-Australian Slang Dictionary (No longer online)

Definitions from Wiktionary (bust one's butt) ▸ verb:  (slang, Canada, US) To work exceptionally hard. ▸ Words similar to bust one's butt ▸ Usage examples for bust one's butt ▸ Idioms related to bust one's butt ▸ Wikipedia articles (New!) ▸ Words that often appear near bust one's butt ▸ Rhymes of bust one's butt ▸ Invented words related to bust one's butt