wanker
verb: to wank noun: wanker adj: wanky
1) someone who jerks off alot
2) someone who does stupid stuff eg falling asleep at the bar, or taking home someone who's so drunk that they then go an piss in the bed
3) term of endearment
4) term of abuse 
1) damn! bill's been in his room for hours! he must be having a wank
2) hahahaaaa what a wanker! 
3) you daft wanker...here, have a beer
4) tony blair is a complete wanker