1. Any of various fat-soluble or water-soluble organic substances that are essential in minute amounts for normal growth and activity of living organisms. They are synthesized by bacteria and plants and are obtained by animals chiefly in their diet.
2. A preparation containing one or more vitamins, often taken as a dietary supplement.
[Alteration of vitamine : Latin vīta, life; see gwei- in the Appendix of Indo-European roots + AMINE (so called because they were originally thought to be amines).]
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