The New Student's Reference Work/Osiris
Osiris (ṓ-sī′rĭs), the greatest of Egyptian gods, is the son of Set (the earth) and Nut (heaven). He was slain by Set, his father, and avenged by his son, Horus. He judges the dead in the lower world. He is represented usually in human form, and always with the head of a man. His symbols are the evergreen and the tamarisk, and a kind of ibis, with long plumes. See Horus, Isis and Set.