In U.S. Marine jargon, a comparative indicating that something is worthless. In more polite company, see hill of beans.
This equipment isn't worth a rat's ass.

So? I don't give a rat's ass.
by Secret Agent Man September 19, 2003
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What you give when you're all out of fucks to give
by J-bird-w May 23, 2017
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To be completely drunk , stonned or otherwise incapable.
Last night i was completely rat-assed.
by zoso May 17, 2005
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To get absolutely wasted from excessive amounts of alcohol.
Dude: Right its friday night and i'm off out to get rat assed tonight.
by Mercifull March 4, 2005
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Zao: Can I have some gravy?
Peng: Certainly.
Peng: Could you pass the rat's ass please...
Chung: There you go.
by lexicon December 19, 2004
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