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

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

From BBC • Apr. 16, 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

I am confused about the difference between vitamin D2 and vitamin D3.

From Seattle Times • Apr. 10, 2024

"Based on our findings, we would recommend that all pregnant women consider a daily intake of at least 4400 IU vitamin D3 throughout their pregnancy, starting at the time of conception."

From Science Daily • Nov. 9, 2023

It triggers the kidneys to inhibit the formation of calcitriol from vitamin D3 and to increase phosphorus excretion.

From Textbooks • Jun. 19, 2013