2. To waste time in an annoying way. Goof off, jerk around, fart around.
3. A person who is distracted and wasting time. Also spelled: jerk-off
4. An insult: something you'd call a person, implying vaguely that the person is clueless or inferior.
"Last night, his girlfriend jerked him off in the car."
"Is our son jerking off again, when he ought to be doing his homework?" (Yeah, the old man meant "goofing off," but he said "jerking off." Heh heh.)
"Hey, jerk-off, quit watching the game and roll some dice."
"That jerk-off? He's a total douchebag."