Definition of "Osirian"

It is, indeed, part of the ritual of the candidate for adeptship into the British mysteries, resembling that for the neophyte into the Osirian, Cabiric or Orphean mysteries.

1928, Lewis Spence, Mysteries of Britain, page v. 123

Nevertheless it is a potentiality, for out of it rises the beetle, the sign for "form" and "coming into being." In the next, the Osirian stage, the night sun penetrates to the Underworld and its rays fall upon the soul in its new form as the body of Osiris.

1981, William Irwin Thompson, The Time Falling Bodies Take to Light: Mythology, Sexuality and the Origins of Culture, London: Rider/Hutchinson & Co., page 242