D defs.my
Entry 1 sense Webster, 1913

niacin

· IPA /ˈnaɪəsɪn/
01 n. A B vitamin (vitamin B5) essential for the normal function of the nervous system and the gastrointestinal tract. Called also nicotinic aci…
  1. 1.
    A B vitamin (vitamin B5) essential for the normal function of the nervous system and the gastrointestinal tract. Called also nicotinic acid and antipellagra vitamin. Chemical formula C6H5NO2, chemically it is 3-pyridinecarboxylic acid. Also: nicotinic acid, antipellagra vitamin
Syn. nicotinic acid.