flip-flop 1 v. , informal To alternate the positions of; exchange the places of; switch. The football coach had one play in which he flip-flopped his left halfback and fullback.
flip-flop 2 n. , informal A complete change; a switch from one thing to an entirely different one. John wanted to be a carpenter like his father, but when he saw the print shop he did a flip-flop and now he's learning printing.
flip-flop 3 adj. phr. , informal Involving or using a change from one of two places, positions, or alternatives to the other. The machine was controlled by a flip-flop switch. The football coach hoped to surprise his opponents by using a flip-flop offense.