In
The Wheel of Time, an
Aes Sedai equivalent of a
Queen.
Amyrlin Seat has supreme authority in the White Tower, at least theoretically. Actually, WT's government is more of parliamentary type: The Hall of Tower has twenty-one sisters: three Sitters from each Ajah. Amyrlin's decisions can be overridden by the Hall and they can even depose Amyrlin if she has acted in secret and on her own, but this been known to happen only a few times, in fact just 3 times since the Breaking of the World.
In The Wheel of Time, a seat in Hall of Tower that Amyrlin Seat (person) sits on.