A broadsword is roughly the same size as a longsword but with a hilt much like a rapier. The term "broad" was added to distinguish this sword from the thin-bladed rapier. Broadswords are also called basket-hilted swords because of the protective cage or basket surrounding the hilt. Early broadswords had just a simple wire guard which became increasingly ornate and covered more of the hand as this weapon evolved. Most broadswords are double-edged but there is a single-edged version called the backsword.
Because of the guard around the hilt, broadswords are one-handed weapons. They require training to wield effectively and are therefore classified as martial weapons. They are used as longswords in all respects.
The Adventurer's Vault source book apparently mentions broadswords. Here is the original entry for this article:
|“||Broadswords are stout, broad heavy blades that are less accurate than the similarly sized, but slightly smaller, longsword but make up for it with increased lethality. Like longswords and bastard swords broadswords are versatile and can be wielded either with one or two hands by human-sized creatures and are more damaging when wielded with two, though at the cost of a shield for defense.||”|
Broadswords are not listed in 2nd Edition or 3.5 Edition Player's Handbooks but 1st Edition lists them as being the same length as a longsword but heavier.