noun. An annoyance; a pet peeve; a pain in the ass.
Real citation: "To answer your question: No, I don’t think a helpful wank is too much to ask from a woman at all. At least you’re not whining about wearing a condom--that’s a major ass-chapper."
(Judy McGuire, New York Press, http://www.nypress.com/17/6/news&columns/date.cfm)
Made-up citation: "My number one ass-chapper is when people say 'Have a blessed day'--it makes me want to claw out everyone's eyeballs."