Doublehand

Two Hands, also known as Doublehand, 2 Handed or Double Grip, is an ability that increases the power of one-handed weapons by holding the weapon in both hands.

Final Fantasy V
Two-Handed is the level 3 ability learned by the Knight job class.

Final Fantasy VI
A character equipped with the Gauntlet Relic can equip a single-handed weapon in both hands.

Final Fantasy Tactics
Doublehand is a support ability learned by the Samurai for 900 JP.

Final Fantasy Tactics Advance
Doublehand is a support ability learnt by the Figher from the Venus Blade.

Final Fantasy Tactics A2: Grimoire of the Rift
Doublehand is a support ability learned by Fighters and Gladiators from the Venus Blade, it requires 300 AP to master and doubles damage.