Assist – The act of one roller derby player helping out another skater on their own team such as whipping skaters or breaking up walls of opposing blockers.
Axle – On a quad skate the axle is the part of the skate that attaches to the wheels and holds them to the truck (see trucks).
Back Block – Making contact or hitting an opponent on the back of the legs, arms or torso outside of the legal blocking zone.
Bearing – An anti-friction apparatus that resides between the wheel and axle of the skate.
Blocker -A roller derby player whose ultimate goal is stopping the other teams jammer. Usually there are 4 blockers from each team occupying the track.