Did you ever tell your parents you were going off to school, grabbed your book bag, and headed out the door... only to spend the rest of the day hanging out with your friends? Well, that was a feint, a super sneaky move designed to fool someone.
Although military and political tactics are big on feints, their most common use is probably in sports — particularly boxing, where opponents are continually trying to fake each other out. As in Dundee's account of an Ali-Frazier match: "Ali feinted with a jab, and Frazier threw one of his own, missing." Not to be confused with faint, meaning "weak or feeble." However, a feint can be deliberately faint, as Ali knew and Frazier found out when the real right hook made contact.