Biochemistry . a compound, CO(NH 2 ) 2 , occurring in urine and other body fluids as a product of protein metabolism.

Chemistry . a water-soluble powder form of this compound, obtained by the reaction of liquid ammonia and liquid carbon dioxide

used as a fertilizer, animal feed, in the synthesis of plastics, resins, and barbiturates, and in medicine as a diuretic and in the diagnosis of kidney function.