The Collaborative International Dictionary of English v.0.48:
Orcus \Orcus\ prop. n. The god of the underworld; counterpart of Greek Pluto. Syn: Dis. [WordNet 1.5]WordNet (r) 3.0 (2006):
Orcus n 1: god of the underworld; counterpart of Greek Pluto [syn: Dis, Orcus]