The term 'Pentathlon Weapon' refers to the type of weapon used in the modern pentathlon, an Olympic sport that consists of five events: fencing, swimming, horse riding, shooting, and running. The weapon used in the fencing event is the epee, a type of sword with a triangular cross-section and a large bell guard. It is heavier than other fencing weapons and is designed for thrusting attacks rather than cutting or slashing.