- (slang, vulgar) Behaviour that is rude, obnoxious, ignorant, or foolish.
- 2007, 4 April, HiC, Re: New member, https://groups.google.com/forum/#!original/rec.music.makers.trumpet/OuQV6imrhnw/M35QGxFL37UJ, rec.music.makers.trumpet, “Well, that and the multiple sockpuppets, blathering on and on and on and on about about not-really "contests" with those who have offended him, and just the whole package of generally oddball assclownery he engages in.”
- 2010, 11 April, Gregg, UFC 112 Thoughts, https://groups.google.com/forum/#!original/alt.ufc/HK6NOZkyaVc/DgWR-U7lnH4J, alt.ufc, “This showboating stuff is assclownery 101- and from the sound of it - the fans didn't think too much for it either and it seems like Dana was a tad pissed off, as he should be.”
- 2010, 15 October, Don Kresch, Re: Rachel Maddow aftermath, https://groups.google.com/forum/#!original/alt.atheism/q0RzNTpb4Dw/Q8oWZsWDdhkJ, alt.atheism, “But you just keep right on whining, little one. And I'll keep right on laughing at your brainwashed assclownery.”