The Genji Blade.
Blades (ブレード, Bureedo?) are a specific type of sword.
Some of Auron's katana are also called Blades.
Blades are used by hume Fighters, Mog Knights, and bangaa Gladiators job classes, and thus are cheaper to acquire at Cyril, Sprohm and Baguba Port.
Blades can be equipped by the Moogle Knight, Fighter, Gladiator, and Heritor job classes. Most have kept their names and abilities taught.