Definition from Wiktionary, the free dictionary
- (vulgar, idiomatic) A jerk; an unpleasant, unlikable person; an asshole.
- At the party he behaved like a real horse's ass.
- (vulgar, idiomatic) A thing or person which is visually unappealing.
- That is one horse's ass of a paint job.
- "horse's ass" in the Dictionary.com Unabridged, v1.0.1, Lexico Publishing Group, 2006.