A friendly gesture in which one person fingers their shithole and jams said crap covered finger into the snotlocker of another. The nose of the recipient then begins to bleed resulting in an explosive stream of blood, snot and poo.
Dirty Red: My asshole itches...

Lil' Be Be: All of this winter weather is causing my nose to dry out....

Dirty Red: JAM!...ha ha....dirty nosebleed....go clean yourself up you stank ass trick....
by Capt Horatio Fellatio January 26, 2011
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