The definition of a vitamin is a substance that is necessary for the processes of the body.
An example of a vitamin is a Vitamin C capsule that someone takes every morning.
See vitamin in Webster's New World College Dictionary
Origin: earlier vitamine < Ger: so named (1913) by C. Funk (1884-1967), Pol biochemist < L vita, life (see vital) + Ger amin, amine: from the orig. mistaken idea that these substances all contain amino acids
See vitamin in American Heritage Dictionary 4
Origin: Alteration of vitamine
Origin: : Latin vīta, life; see gwei- in Indo-European roots
Origin: + amine (so called because they were originally thought to be amines).
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