A vitamin is an organic substance your body needs to keep working properly. Vitamins are important to health.

Your body needs food and water to stay alive, but it also needs vitamins to work properly. You get some Vitamin D from the sun, and lots of Vitamin C from citrus fruits such as oranges. Without vitamins, your immune system can weaken. Many people take vitamins in pill form to help them stay healthy. The word vitamin — originally vitamine — was coined by scientist Casimir Funk in the early 1900s. He combined vita, Latin for "life," with amine, from amino acids.

Definitions of vitamin
  1. noun
    any of a group of organic substances essential in small quantities to normal metabolism
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    fat-soluble vitamin
    any vitamin that is soluble in fats
    water-soluble vitamin
    any vitamin that is soluble in water
    A, antiophthalmic factor, axerophthol, vitamin A
    any of several fat-soluble vitamins essential for normal vision; prevents night blindness or inflammation or dryness of the eyes
    B, B complex, B vitamin, B-complex vitamin, vitamin B, vitamin B complex
    originally thought to be a single vitamin but now separated into several B vitamins
    D, calciferol, cholecalciferol, ergocalciferol, viosterol, vitamin D
    a fat-soluble vitamin that prevents rickets
    E, tocopherol, vitamin E
    a fat-soluble vitamin that is essential for normal reproduction; an important antioxidant that neutralizes free radicals in the body
    antihemorrhagic factor, naphthoquinone, vitamin K
    a fat-soluble vitamin that helps in the clotting of blood
    bioflavinoid, citrin, vitamin P
    a vitamin that maintains the resistance of cell and capillary walls to permeation
    C, ascorbic acid, vitamin C
    a vitamin found in fresh fruits (especially citrus fruits) and vegetables; prevents scurvy
    type of:
    aliment, alimentation, nourishment, nutriment, nutrition, sustenance, victuals
    a source of materials to nourish the body
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