cock a snook(British) 1. to make a rude gesture by putting one thumb to the nose with the fingers of the hand outstretched 2. to show contempt by being insulting or offensive. Collins. or cock snooks also cock a snoot • to thumb the nose: an unmannerly upstart cocking snooks at venerable men – Adrian Bell; in the Highlands where they traditionally cock a snoot at rationing laws – John Calder. WTNI. Alexander Demidov)