- a colorless, crystalline, water-soluble solid, C6H6N2O, the amide of nicotinic acid, and a component of the vitamin-B complex, found in meat, liver, fish, whole wheat, and eggs: used in medicine chiefly as an agent for preventing or treating human pellagra or animal black tongue.
- the amide of nicotinic acid: a component of the vitamin B complex and essential in the diet for the prevention of pellagra. Formula: C 6 H 6 ON 2
