1 definition by mr.seed

cum block

Similar to a cock block, this is the act of walking in someone (usually a male friend) while they are having sex, to stop them from making it all the way.

Guy 1: "I was rooting this chick the other night, I was about to blow but my mate walked in and totally cum blocked me."

Guy 2: "Tough luck man."

by mr.seed May 12, 2008