vitamin D

American  

noun

1. any of the several fat-soluble, antirachitic vitamins D 1 , D 2 , D 3 , occurring in milk and fish-liver oils, especially cod and halibut, or obtained by irradiating provitamin D with ultraviolet light, essential for the formation of normal bones and teeth.

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vitamin D British  

noun

1. any of the fat-soluble vitamins, including calciferol and cholecalciferol, occurring in fish-liver oils (esp cod-liver oil), milk, butter, and eggs: used in the treatment of rickets and osteomalacia

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vitamin D Scientific  

1. Any of a group of fat-soluble sterols necessary for normal bone growth, especially vitamin D ₂ (ergocalciferol) and vitamin D ₃ (cholecalciferol). Vitamin D is found in milk, fish, and eggs and can be produced in the skin on exposure to sunlight. A deficiency of vitamin D in the diet causes rickets in children.

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Etymology

Origin of vitamin D

First recorded in 1920–25

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Example Sentences

See Examples For:

vitamin D

During the winter months, people start to lose their vitamin D levels.

From BBC ● Oct. 30, 2026

She remembers her mother suffering from low vitamin D but says she did not realise it could happen to her.

From BBC ● Oct. 30, 2026

If you’re at risk for osteoporosis or bone issues, you can also opt to take calcium and vitamin D supplements.

From The Wall Street Journal ● Oct. 12, 2026

People who avoid dairy should make sure they get enough calcium and vitamin D from other foods.

From The Wall Street Journal ● Oct. 12, 2026

He needed vitamin D for the boy or he was going to get rickets.

From "The Road" by Cormac McCarthy

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