vitamin D3

American  

noun

1. a D vitamin, C 27 H 43 OH, occurring in fish-liver oils, that differs from vitamin D 2 by slight structural differences in the molecule.

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vitamin D3 British  

noun

1. another name for cholecalciferol

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vitamin D3 Scientific  

1. A colorless, crystalline steroid hormone that the body synthesizes in the skin when its precursor, a derivative of cholesterol, is irradiated by sunlight. Vitamin D ₃ is also found in fish-liver oils, irradiated milk, and all irradiated animal foodstuffs. Also called calciferol, cholecalciferol. Chemical formula: C ₂₇ H ₄₄ O.

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Example Sentences

See Examples For:

vitamin D3

Cognitive performance was similar among people taking vitamin D2, which is typically obtained from plants or fungi, and vitamin D3, which the body produces after sun exposure and which can also come from animal-based foods.

From Science Daily ● Aug. 23, 2026

Taking vitamin D2 might lower the body's levels of the more efficient form of vitamin D, vitamin D3, according to new research from the University of Surrey, John Innes Centre and Quadram Institute Bioscience.

From Science Daily ● May 23, 2026

Further research into the different functionalities of vitamin D2 and D3 should be a priority in deciding whether vitamin D3 should be the first-line choice of vitamin D supplement, subject to individual requirements.

From Science Daily ● May 23, 2026

A colleague in Manchester had asked him if they had seen any of a "bad batch" of vitamin D3.

From BBC ● Apr. 16, 2026

He was given supplements containing vitamin D3 – also known as colecalciferol – to raise the levels in his blood.

From BBC ● Apr. 16, 2026