The term 'Thin Sword' is used to describe two types of swords: the RAPIER (6 letters) and the epee (4 letters). The RAPIER is a slender, sharply pointed sword that was popular in Europe during the 16th and 17th centuries. It was primarily used for thrusting attacks and was often used in duels. The epee is a modern version of the RAPIER and is used in fencing competitions. It is a thrusting weapon with a triangular cross-section and a large bell guard. Both the RAPIER and the epee are considered thin swords due to their slender design.