vitamin D

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.

vitamin D

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

vitamin D

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.

Word History and Origins

Origin of vitamin D¹

First recorded in 1920–25

Example Sentences

In the past, most individuals received sufficient vitamin D through sunlight exposure.

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A new review suggests that vitamin D supplements may help protect the ends of our chromosomes, known as telomeres, which play a vital role in slowing the aging process.

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If you add the functional ingredients to a category that isn’t perceived as part of the health regime—say, adding vitamin D to breath mints—it would be less successful.

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Some UV radiation is crucial for our wellbeing, enabling our skin to produce essential vitamin D, but too much can be dangerous.

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He probably just needed some downtime, decompressing, healthy juices and vitamin D to get him back on track.

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