The act of shifting a motor vehicle into reverse gear while on a highway in order to back up and to get onto an exit ramp one has already passed. This term comes from the New York Metro area, where Asians and Caucasians have conducted a nonscientific study by looking to see what the person taking this action looked like only to find that they are black at least 90% of the time.
by ISwearIMnotRacist June 11, 2013
the traffic caused by a group of African Americans blocking the hall and preventing Caucasian students from moving to their next class.
Tom: Dude, why arent we moving?????
Andrew: Man this is the Math hall. This is probably the black-up from all those black guys who walk slowly.
Andrew: Man this is the Math hall. This is probably the black-up from all those black guys who walk slowly.
by FlockaFlocka12 February 03, 2011
After Joe made a racist joke at KFC, he soon drew a crowd and was blacked up on the spot. His friends claimed they never knew Joe in order to avoid being blacked up.
by Nevets November 16, 2007
An act of aggression that occurs "when fools need a beating, and you call your homies, and put in some work."
by Rihanna had it coming January 24, 2011
by AzraelNarianErnee September 19, 2013
A black up plan can only be observed.
"What the hell, you're 2 weeks pregnant?!? Where's my boxing gloves."
"What the hell, you're 2 weeks pregnant?!? Where's my boxing gloves."
by bpiau2728 February 04, 2012
by LukeAndShet November 27, 2010