RhymeZone: demi definitions

Definitions of Demi:

noun: A female given name, a diminutive of Demetria introduced into English in the 1990s by the actress Demi Moore.
noun: (slang) A fifty pence piece.
noun: A bottle of wine containing 0.375 liters of fluid, 1/2 the volume of a standard bottle; a split.
adjective: (informal) Demisexual.
noun: Alternative spelling of demy. [A printing paper size, 17½ inches by 22½ inches.]

(Definitions from Wiktionary)