巨人のなめし革 [kyojin no nameshigawa] or 'giants' tanned hide' in Japanese. The name can mean either that the hide of a giant was tanned, or that giants tanned a hide. Based on description, either meaning would work, depending on the game.
Final Fantasy XII
Buy: - (sell: 672 gil)
Use: Chakra Band & Power Vest, Platinum Helm & Platinum Armor & Platinum Shield
Drop: Humbaba, Slaven Warder, Slaven Wilder, Yeti
Steal: Atomos, Slaven Wilder, Yeti
Poach: Humbaba, Slaven Warder, Slaven Wilder, Werewolf, Yeti, Zaghnal
Description: The tanned skin of a member of the race of giants. While of low quality, the feel of a giantskin garment cannot be matched. Neither, however, can the stench.
Grimoire of the Rift

Buy: - (sell: 400 gil)
Use: Beastsword, Dream Claws, Eight of Hearts, Kaiser Knuckles, Power Sash
Reward: Speed Battle, Kupo! x5 (repeatable)
Type: Skin, Rank: ★
Description: The techniques for tanning these large hides have been passed down by the giants for centuries. The finished product is a bit tough.
Final Fantasy Tactics S

Buy: - (sell: 50 gil)
Use: Leather Clothing
Obtain: Cend Region/Aquamarine Highroad
Description: A somewhat uncommon skin
Category: Item