The Collaborative International Dictionary of English v.0.48:
Nephthys \Nephthys\ prop. n. The goddess associated with ritual of the dead; sister of Geb and Nut; wife of Set. [WordNet 1.5]WordNet (r) 3.0 (2006):
Nephthys n 1: Egyptian goddess associated with ritual of the dead; sister of Geb and Nut; wife of Set