diaphorase Syllabification: (di·aph·o·rase)Pronunciation: /dīˈafəˌrās, -ˌrāz/Definition of diaphorase noun Biochemistry an enzyme of the flavoprotein type, able to oxidize a reduced form of the coenzyme NAD. Origin: 1930s: from Greek diaphoros 'different' + -asediaphorase in other Oxford dictionaries Definition of diaphorase in the British & World English dictionary