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

There are two forms of vitamin D supplements available: vitamin D2 and vitamin D3.

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

Roo was prescribed a high dose of vitamin D3 drops for 12 weeks in December 2024 to try to ease intense pain in his legs.

From BBC ● Apr. 16, 2026

Today, with lifestyle changes and medical advice aimed at reducing skin cancer risk, people spend less time in the sun and must rely more on dietary supplements such as vitamin D3 to maintain healthy levels.

From Science Daily ● Nov. 10, 2025

"We observed no adverse outcomes when giving patients higher doses of vitamin D3 supplementation, and to significantly reduce the risk of another heart attack, which are exciting results," said Dr. May.

From Science Daily ● Nov. 10, 2025