Blocker can mean any of the following:Blocker (ice hockey equipment)The nickname of Steve Roach, Australian rugby league footballer Blocker (cricket), slang for a defensive-minded batsman in cricketThe inverse of a filter (optics). Instead of blocking everything except target color(s) like a filter does, a blocker lets everything else pass and blocks only the color(s) specified.Blocker (roller derby) is a position in roller derby.Terry Blocker is a former major league baseball player… (More on Blocker)