: a vitamin C12H17N4OSCl of the vitamin B complex that is an amino hydroxy quaternary ammonium water-soluble salt containing a thiazole ring and a pyrimidine ring, that occurs widely both free (as in the germs of cereals and hulls of grain) and combined (as in yeast and in animal tissu...
Medical Definition vitamin B noun 1 : vitamin b complex 2 : any of numerous members of the vitamin B complex especially : thiamine Last Updated: 13 Dec 2024 - Updated example sentences Love words? Need even more definitions? Subscribe to America's largest dictionary and get thousands ...