The Avari were Elves who refused the summons of the Valar and remained in the darkness of Middle-earth. Their name means "those who refused the summons", though "the unwilling" is also commonly seen.

In early stories, Tolkien had some of the Avari being corrupted by Melkor in ancient days to become the progenitors of the race of Orcs.

The Avari were also part of the Moriquendi, or dark elves, because they never saw the light of the trees in Valinor.
Encyclopedia entry originally written by Nanelleth