Rossco Share definition Flag The art of having a wank whilst your partner is asleep next to you. The Rossco can be performed anywhere, usually silently. "the missus fell asleep infornt of the telly again so I had a Rossco" Rossco by Dan Shering March 12, 2008 0 0 Get merch Get the Rossco mug. Buy Now — $32.95 See more merch