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

In many of the studies, the vitamin D3 levels went lower than in the control group.

From Science Daily • May 23, 2026

Roo's bottle of vitamin D3 drops - which were about seven times more concentrated than they should have been - was from one of two bad batches distributed across the UK.

From BBC • Apr. 16, 2026

A month before Roo began his course of vitamin D3 drops, Kayan Khan from Sheffield had also been prescribed the same brand of supplements.

From BBC • Apr. 16, 2026

A new study from Intermountain Health in Salt Lake City reports that a personalized vitamin D3 treatment plan for patients who have suffered a heart attack can greatly reduce their chances of another one.

From Science Daily • Nov. 10, 2025

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