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

Common hazards include prescription and over-the-counter medications, vitamins, cleaning and laundry products, cosmetics, pesticides, automotive fluids, and batteries. — Katia Hetter, CNN Money, 10 Sep. 2026

Leafy greens like spinach and kale contain vitamin K1, whereas specific animal products and fermented foods provide vitamin K2. — Lauren Panoff, Verywell Health, 9 Sep. 2026

As someone with genetic hyperpigmentation (aka many, many freckles), I was also intrigued by the way vitamin C eases discoloration. — Maggie Ryan, Flow Space, 4 Sep. 2026

Elderberry helps fight and relieve the symptoms of common colds and touches of flu with its rich combination of vitamins and nutritional properties. — Bestreviews, Chicago Tribune, 4 Sep. 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 B6
• vitamin B complex
• vitamin C
• vitamin D3
• vitamin E
• vitamin H
• vitamin K3

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