skagg knacker Share definition Flag A Heroin Addict who has used all available veins in his arms and legs, and has resorted to injecting into his scrotum. "Look at the state of that guy, I bet he`s a skagg knacker!" skagg knacker by Yea Yeah October 1, 2006 0 0 Get merch Get the skagg knacker mug. Buy Now — $32.95 See more merch