What is "vlaakith"

In the Dungeons & Dragons fantasy roleplaying game, Vlaakith (pronounced ) is the name of the first ruler of the githyanki race after the disappearance of Gith, the rebel leader that united them against the illithids. Vlaakith CLVII, also known as the Lich-Queen (or, by her followers, as the Revered Queen), is the current ruler of the githyanki, and is a fictional character and adversary in the game.