1. A term derived from the movie "Gridiron Gang" in which "88" is used to identify like members of the gang that bears the "88" name.
2. Popularized by an influential group of high school student's, who used the term copiously in their day-to-day speak, to denote many different forms/dispositions of interaction. Considering this, "88" has become highly reliant on identifying vocal subtleties and body language. The most frequent display of "88" body language is the act of shaping ones thumb, index, and middle fingers in to respective 8 shapes and then merging the 8s at the knuckles.
(When saying hello to a companion): 88 muthafucka!
(When saying farewell): Catch you later, 88.
(When proclaiming a death threat on members of opposing factions): 88! Ride or die!
(When experiencing loss and/or dejection): Fucking 88 man.