Níniel (or Nienor) was a daughter of Húrin and Morwen. When she was with her mother searching for her brother Túrin, she got lost and the dragon Glaurung put a black spell on her that made her forget everything.

She ran away to the Forest of Brethil, and Túrin found her lying there. Nienor couldn't tell anything about herself and all she did was cry. Then Túrin gave her the name Níniel, "The Tear-maiden". Túrin took her with him and married her.

She was called Níniel until Túrin killed Glaurung and the spell was lifted. Then she remembered her name and all that had happened, and she killed herself by jumping into Cabed Naeramarth.
Encyclopedia entry originally written by AinarielPalantir