[ vahy-tuh-min; British also vit-uh-min ]
See synonyms for vitamin on
  1. any of a group of organic substances essential in small quantities to normal metabolism, found in minute amounts in natural foodstuffs or sometimes produced synthetically: deficiencies of vitamins produce specific disorders.

Origin of vitamin

1912; earlier vitamine<Latin vīt(a) life + amine; coined by C. Funk, who thought they were amines
  • Also vi·ta·mine [vahy-tuh-min, -meen; British also vit-uh-min, -meen]. /ˈvaɪ tə mɪn, -ˌmin; British also ˈvɪt ə mɪn, -ˌmin/.

Other words from vitamin

  • vi·ta·min·ic, adjective

Words Nearby vitamin Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

How to use vitamin in a sentence

  • They carefully devised vitamin-free, protein-free, mineral-free diets that tasted like library paste and smelled worse.

    The Coffin Cure | Alan Edward Nourse
  • Digestibility, as well as protein, mineral and vitamin requirements, must also be considered.

    How to Live | Irving Fisher and Eugene Fisk
  • vitamin B complex, vitamin C—and, finally, half a dozen highly questionable contraceptive pills?

    Inside John Barth | William W. Stuart
  • The essential element of foods is the vitamin, a nitrogenous substance of indeterminate nature.

  • Moreover, he had isolated a vitamin in this protein not found in any of man's present foods.

British Dictionary definitions for vitamin


/ (ˈvɪtəmɪn, ˈvaɪ-) /

  1. any of a group of substances that are essential, in small quantities, for the normal functioning of metabolism in the body. They cannot usually be synthesized in the body but they occur naturally in certain foods: insufficient supply of any particular vitamin results in a deficiency disease

Origin of vitamin

C20: vit- from Latin vīta life + -amin from amine; so named by Casimir Funk, who believed the substances to be amines

Derived forms of vitamin

  • vitaminic, adjective

Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Scientific definitions for vitamin


[ tə-mĭn ]

  1. Any of various organic compounds that are needed in small amounts for normal growth and activity of the body. Most vitamins cannot be synthesized by the body, but are found naturally in foods obtained from plants and animals. Vitamins are either water-soluble or fat-soluble. Most water-soluble vitamins, such as the vitamin B complex, act as catalysts and coenzymes in metabolic processes and energy transfer and are excreted fairly rapidly. Fat-soluble vitamins, such as vitamins A, D, and E are necessary for the function or structural integrity of specific body tissues and membranes and are retained in the body.

a closer look

Although it has been known for thousands of years that certain diseases can be treated with specific foods, the scientific link between vitamins and good health wasn't made until the early 1900s by Polish-born American biochemist Casimir Funk. While studying beriberi, a disease that causes depression, fatigue, and nerve damage, Funk discovered an organic compound in rice husks that prevents the illness. He named the compound vitamine, derived from the chemical name amine and the Latin word vita, "life," because vitamins are required for life and were originally thought to be amines. Funk's compound is now known as vitamin B1, or thiamine. His research and discovery led him, along with English biochemist Sir Frederick Gowland Hopkins, to propose the vitamin hypothesis of deficiency, which stated that certain diseases, such as scurvy or rickets, are caused by dietary deficiencies and can be avoided by taking vitamins. Further research allowed scientists to isolate and identify the vitamins that we know today to be essential for human health. Vitamins include A, C, D, E, K, thiamine, riboflavin, niacin, B6, B12, folic acid, biotin, and pantothenic acid. Vitamins are distinguished from minerals, such as calcium, iron, and magnesium, which are also essential for optimum health.

The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.