エーテル水 [ether mizu] or 'ether water' in Japanese.
Final Fantasy XII
Buy: - (sell: 1,783 gil)
Use: Ether, Hi-Ether
Drop: Hecteyes
Poach: Etherian, Hecteyes
Description: This liquid is lighter than air itself. Look at it from different angles and it changes hue from a scintillating crimson to a glowing azure.
Revenant Wings
Buy: - (sell: 3,240 gil)
Shop: -
Use: Divider, Fumarole, Polaris, Rainmaker, Tumulus, Wizard's Rod
Obtain: mission 7-1 (harvest 22%), 8-3 (reward 75% with Goblin Pouch) Feol Warren Monster Melee (harvest 22%)
Description: Fluid lighter and more lucid than air. Seen from the right angle, it shimmers iridescently.
Other: mid-grade Aqueous Fluid
Grimoire of the Rift

Buy: - (sell: 1,000 gil)
Use: Ace of Spades, Blueleaf Flute, Godhand, Life Crosier, Mjolnir
Reward: Rancher's Request - Brown x3 (once), To Be a Spellblade x2 (once)
Type: Philtre, Rank: ★★
Description: A scintillating liquid, lighter than air itself. Under light, it sparkles with all the colors of the rainbow.
Final Fantasy Tactics S

Buy: - (sell: 200 gil)
Use: Ashura
Obtain: Western Orda Woodsea/The Spirit Pond lv30+
Description: An uncommon substance
Category: Item