Someone who is ridiculously dumb, make an ass of themselves, and hasn't got a clue about what's going on around them. However, tools are usually used and kept around for either entertainment purposes (ie. getting them to do something really stupid for laughs) or for other things (ie. transportation).
Phil: Hey, that Dick guy, he's a fuckin' tool! He sings "I'm a Little Tea Pot" when I tell him to. Bob: Yeah, that's the only reason we keep that tool around.
By brouhaha
Typically a male who gels his hair every morning and makes sure everything he wears is designer brand and that people know it. All of his thoughts are centered around himself and he believes everyone else's should be too. He tries hard to be that cool, popular guy that loves, yet he is not. He thinks that if a girl doesnt go for him, it is only because she has a boyfriend but secretly wishes she could have him anyway.
Wheres Matt? Hitting on that drunk girl over there Oh man what a tool.
By khags
One who calls others tools and yet does not realize that they are a tool.
-Your such a tool -I'm not the one giving free stuff to people you barely know
By Petitekimbyswimmerscreek
someone who tries too hard. a poser. one of those chic's who holds the sign saying "Carson Daly is Hot." the asstard who goes to a rock show because they heard one of the songs on the radio or mtv. or someone who insists on wearing velour sweat suits. Avril Lavigne.
Tripp Moss is a fucking tool.
By Tool Detector
One lacking social awareness or ignoring their own mental capacity to realize when they're a pawn to unsustainable corporate interests. A slave and/or sell-out to the globalization of business power.
That tool doesn't even know he's toeing the line.
By gnuosphere