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noun ni·a·cin \ˈnī-ə-sən\

: a type of natural substance (called a vitamin) that is found in certain foods and that helps your body to be healthy

Full Definition of NIACIN

:  an acid C6H5NO2 of the vitamin B complex found widely in animals and plants and used especially against pellagra; also :  nicotinamide —called also nicotinic acid

Origin of NIACIN

nicotinic acid + 1-in
First Known Use: 1942
Medical Dictionary


noun ni·a·cin \ˈnī-ə-sən\

Medical Definition of NIACIN

:  a crystalline acid C6H5NO2 that is a member of the vitamin B complex occurring usually in the form of a complex of niacinamide in various animal and plant parts (as blood, liver, yeast, bran, and legumes) and is effective in preventing and treating human pellagra and blacktongue of dogs—called also nicotinic acid


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