a person who tries too hard to fit in, poses, is easily and obliviously used and is in general just a stupid fuck. so much to the point that this person isn't just a tool, they're equivalent to an entire sack of tool. therefore, they're a toolsack.
Phil "Dude, you ever notice Ike is always trying to one-up me when we talk about wake boarding?"

Joe "Yeah, because he's a massive toolsack!"
by Amfeezy October 10, 2006
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