Demogorgon
/ˌdiːmə(ʊ)ˈɡɔːɡ(ə)n/noun
1 Mythology (The name of) a powerful and terrible god or demon, associated with hell or the underworld.
2A person who or thing which is likened to Demogorgon, especially in having absolute power or supremacy.
Origin
Mid 16th century; earliest use found in David Lindsay (c1486–1555), writer and herald. From post-classical Latin Demogorgon, scribal error in scholia on Statius Thebaid 4. 516 for demiurgon, accusative of demiurgos.