The term flamberge, meaning "flame blade", is an undulating blade found on both long blades and rapiers. When parrying with such a sword, unpleasant vibrations may be transmitted into the attacker's blade. These vibrations caused the blades to slow contact with each other, as additional friction was encountered with each wave. The term flamberge was misapplied to refer to two-handed swords and was used later to refer to cup hilt rapiers with a straight blade.
Read more about this topic: Flame-bladed Sword