In a combat sport like paintball or airsoft, or First Person Shooter like Call of Duty or Brothers In Arms, a person (usually a sniper or camper) who stays behind or takes refuge behind or near a tree. Conied by the US Army Sniper School.
Troy was a tree cancer when he stayed behind a tree and sniped for 20 minutes in Call of Duty.
by Hackermeyer March 29, 2009
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