any of a class of aromatic yellow compounds including several that are biologically important as coenzymes or acceptors or vitamins; used in making dyes
A crystalline substance, C6H4O2 (called also benzoketone), first obtained by the oxidation of quinic acid and regarded as a double ketone; also, by extension, any one of the series of which quinone proper is the type
{i} chinone, cyclic unsaturated diketone, yellow crystalline compound used in photography and the manufacture of dyes (Chemistry); any class of organic compound found as a pigment (yellow, orange or red) in plants and bacteria and also found as animal vitamins
Any member of a class of cyclic organic compounds comprising a six-membered unsaturated ring (see saturation) to which two oxygen atoms are bonded as carbonyl groups (CO; see functional group). This structure plays an important role in theories of chemical structure and colour, since quinones occur as pigments in bacteria, fungi, and certain higher plants; animals containing quinones obtain them from plants they eat. The K vitamins (see vitamin K) are naphthoquinones. The term quinone often specifically denotes para-benzoquinone (C6H4O2), a bright yellow solid with a sharp odour used in manufacturing dyes and fungicides and in photography