1
general::
Get rid of by work or effort, as in They worked off that big dinner by running on the beach, or It'll take him months to work off that debt. [Second half of 1600s]
American Heritage Idioms
2
general::
Phrase(s): work something off
1. Lit. to get rid of anger, anxiety, or energy by doing physical activity. • I was so mad! I went out and played basketball to work my anger off. • He works off nervousness by knitting. 2. Fig. to pay off a debt through work rather than by money. • I had no money so I had to work the bill off by washing dishes. • I have to work off my debt.
McGrawhill's American Idioms And Phrasal Verbs