noun
also vi·ta·mine ˈvīd.əmə̇n, -ītəm-
( -s )
Usage: often attributive
Etymology: International Scientific Vocabulary vit- (from Latin vita life) + amine; probably originally formed in German; from the former belief that such substances were amines — more at vital
: any of various organic substances that individually or collectively are as far as is known essential to the nutrition of vertebrates, some invertebrates, many microorganisms, but prob. not most higher plants, that act typically in minute amounts in the regulation of various metabolic processes but do not provide energy or serve as building units, that are present in small amounts in various natural foodstuffs and are sometimes produced within the body (as by the action of intestinal bacteria in the rat) but are not ordinarily synthesized or stored in quantity in the human body, that may be detected as deficient in a particular organism by specific symptoms which can be relieved by administration of the appropriate vitamin, and that are commonly classified according to their water or fat solubility, their physiologic effects, or their chemical structure — see antivitamin , avitaminosis , provitamin ; compare auxin , growth factor