Order of Maesters (Earth-6120)

The Order of Maesters, also known as the Maesters of the Citadel, the Knights of the Mind, and most often simply as the Maesters, are an order of intellectuals (scholars, healers, and other learned men) in the Seven Kingdoms.

Focusing on scientific knowledge and disdaining belief in magic, in the present day the Order of Maesters has largely eclipsed the older Alchemists' Guild, which claims to possess arcane magical knowledge, but whose number, power, and abilities have waned over the centuries.

The maesters are a secular organization, not a religious order, though they do swear sacred oaths to follow the duties and restrictions of their office. Unlike certain other organizations such as the Brotherhood of Sorcerers and the Faith of the Seven, which has male and female members, women are not allowed to join the maesters.

Source

 * https://gameofthrones.fandom.com/wiki/Maesters