1: The act slapping someone with ones flaccid penis; usually, though not always across the face. The optimal jimmy slap leaves a damp, phallic shaped mark where the phallus made contact with its victim, though this is not mandatory.
Alex passed out at the party so John jimmy slapped him and took a Polaroid.
when a drunk redneck announces to a party that he intends to "smack" someone sitting on the other side of the room because that person is either (a) wearing an obnoxious hat; (b) appears to be gay; or (c) makes the drunk redneck question his own sexuality, and then the drunk redneck strolls and stumbles across the room and smacks that person.
Tom told Matt and Stephanie that he was 'gonna smack' Jim, and then he walked over and jimmyslapped him.