work one's tail off, to

work one's tail off

 and work one's buns off; work one's ass off; work one's butt off
Inf. Fig. to work very hard. (Use caution with butt.) I worked my tail off to get done on time. You spend half your life working your butt off—and for what?
See also: off, tail, work
McGraw-Hill Dictionary of American Idioms and Phrasal Verbs. © 2002 by The McGraw-Hill Companies, Inc.

work one's tail off, to

To work very hard. This inelegant locution dates from the first half of the twentieth century. James Farrell used it in Studs Lonigan (1932–35): “This idea of sweating your tail off with work.” It also is put as to work one’s ass or butt off. See also break/bust one's ass.
See also: tail, work
The Dictionary of Clichés by Christine Ammer Copyright © 2013 by Christine Ammer
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