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

See Examples For:

vitamin D

These factors include age, sex, ethnicity, body mass index, smoking status, existing medical conditions, previous muscle problems, vitamin D deficiency, medication use, and whether a person has been prescribed statins.

From Science Daily ● Jun. 30, 2026

The findings challenge the widely held belief that spending time in the summer sun is enough to restore healthy vitamin D levels.

From Science Daily ● Jun. 24, 2026

Perhaps most notably, vitamin D levels did not improve during the summer months.

From Science Daily ● Jun. 24, 2026

Rajan takes vitamin D, a prebiotic, protein, fibre and creatine - in what he describes as a "supplement stack" - to target areas where he could have a deficiency.

From BBC ● Jun. 20, 2026

It’s sunny outside today-I know, I'm shocked, too-so I'm going to go outside and soak up as much vitamin D as I can.

From "Twilight" by Stephenie Meyer