Apparently, it's NBA lingo for a "hesitation-dribble and two steps." Basically, it's just the hottest thing on the market to say when you travel in basketball...but want to get away with it.
Fan #1 "Dude, did you see LeBron totally get away with travelling on that last basket?"
Fan #2 "No, dude...that was totally a 'crab dribble' asshole. LeBron's the Chosen One.
Fan #1 "You're retarded. Get the fuck outta my face. Now."
Fan #2 "No, dude. Watch."
Fan #1 "Hey...he fuckin' travelled and got away with it alright? Shut up. PLEASE."