What is "rerir"

In Völsunga saga, Rerir, the son of Sigi, succeeds his murdered father and avenges his death. He rules the Huns in Hunaland and becomes a powerful ruler. Rerir's son is Völsung.

Rerir and his wife were unable to have children until the goddess Frigg, the wife of Odin sends them a giantess named Hljod in the shape of a crow to deliver an apple of fertility to the couple. Shortly after, Rerir’s wife becomes pregnant but he becomes ill and dies. His wife remains pregnant for six years, until she realizes she will not live much longer and commands that the child be delivered with a Caesarian, an operation that in those days cost the life of the mother. When the child, Völsung, was delivered he was already well grown and he “kissed his mother before she died.”

Mount Rerir is a location in the fictional world of Middle-earth.