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

Example Sentences

The team also did not measure inflammatory markers that might explain how vitamin D influences pain.

From Science Daily • May 20, 2026

Patients with low vitamin D used an average of 112mg more tramadol than those with sufficient vitamin D levels.

From Science Daily • May 20, 2026

Researchers in Brazil have found that a simple vitamin D supplement may help chemotherapy work better in women with breast cancer.

From Science Daily • Apr. 28, 2026

The body produces vitamin D mainly through sunlight exposure, and it can also be obtained through certain foods.

From Science Daily • Apr. 28, 2026

“You can’t stay holed up in this apartment. What about friends? What about fresh air? She probably has a vitamin D deficiency.”

From "The Miscalculations of Lightning Girl" by Stacy McAnulty