flavoproteinPronunciation: /ˌfleɪvə(ʊ)ˈprəʊtiːn/Definition of flavoprotein noun Biochemistry any of a class of conjugated proteins that contain flavins and are involved in oxidation reactions in cells. Origin: 1930s: blend of flavin and proteinflavoprotein in other Oxford dictionaries Definition of flavoprotein in the US English dictionary