vitamin

noun

vi·​ta·​min ˈvī-tə-mən 

British usually

ˈvi- 

: any of various organic substances that are essential in minute quantities to the nutrition of most animals and some plants, act especially as coenzymes and precursors of coenzymes in the regulation of metabolic processes but do not provide energy or serve as building units, and are present in natural foodstuffs or sometimes produced within the body

Examples of vitamin in a Sentence

This cereal contains essential vitamins and minerals.

Did you remember to take your vitamin?

Recent Examples on the Web

This enzyme cleaves the ester bonds in the neuronal portion of the back retina—the retinal pigment epithelium— to create a usable form of vitamin A, a molecule called 11-cis-retinal. —Lauren J. Young, Scientific American, 4 May 2026

Keep in mind that both types of pasta contain important nutrients, such as protein, fiber, iron, and other vitamins and minerals. —Brittany Lubeck, Verywell Health, 4 May 2026

Aloe is chock-full of vitamins and fatty acids. —Bestreviews, Mercury News, 4 May 2026

The vitamin and wellness section is known for wide variety of supplements. —Samantha Gowen, Oc Register, 4 May 2026

Word History

Etymology

alteration of vitamine, from Latin vita life + English amine

First Known Use

circa 1912, in the meaning defined above

Phrases Containing vitamin

• B vitamin
• vitamin A
• vitamin B
• vitamin B complex
• vitamin C
• vitamin D
• vitamin E
• vitamin H
• vitamin K

Kids Definition

vitamin

noun

vi·​ta·​min ˈvīt-ə-mən 

: any of various substances that are necessary in very small amounts to the nutrition of most animals and some plants, that are important to the control of growth and development by activating and assisting in the function of enzymes, and that are present naturally in many foods or in some cases are produced within the body

Medical Definition

vitamin

noun

vi·​ta·​min ˈvīt-ə-mən, British also ˈvit- 

: any of various organic substances that are essential in minute quantities to the nutrition of most animals and some plants, act especially as coenzymes and precursors of coenzymes in the regulation of metabolic processes but do not provide energy or serve as building units, and are present in natural foodstuffs or are sometimes produced within the body