Ithryn Luin meant "Blue Wizards," and was the collective name for two members of the Istari. When they came to Middle-earth, they were robed in sea-blue, hence the term.

They were identified as Pallando and Alatar, both Maiar of Oromë's following. They traveled to the far east with Saruman the White, but they never came back to the westlands and were never heard from again.