GR'd up Share definition Flag To buy a one gram (or several) of either high potency marijuana or cocaine. Derives from the abbrevation for a gram - GR. I stopped my my boy's crib who grows that chronic and got GR'd up. GR'd up by Fuzzycom April 7, 2006 0 0 Get merch Get the GR'd up mug. Buy Now — $32.95 See more merch