vitamin D

noun

: any or all of several fat-soluble vitamins chemically related to steroids, essential for normal bone and tooth structure, and found especially in fish-liver oils, egg yolk, and milk or produced by activation (as by ultraviolet irradiation) of sterols: such as

a

or vitamin D₂

-ˈdē-ˈtü 

: calciferol

b

or vitamin D₃

-ˈdē-ˈthrē 

: cholecalciferol

Examples of vitamin D in a Sentence

Recent Examples on the Web

Calcium and vitamin D are essential for bone health. —Jianying Zhang, Discover Magazine, 8 Nov. 2024

Sardines are also a good source of calcium and vitamin D, crucial for fetal bone health during pregnancy. —Lana Barhum, Verywell Health, 31 Oct. 2024

However, it's recommended that adults take in 15 micrograms of vitamin D through their diet each day. —Merve Ceylan, Health, 21 Oct. 2024

There have been no reports of adverse events attributed to the elevated levels of vitamin D in the recalled product, according to the FDA, which was determined through routine testing. —Chad Murphy, The Enquirer, 28 Oct. 2024

Word History

First Known Use

circa 1921, in the meaning defined above

Kids Definition

vitamin D

noun

: any of several vitamins that are needed for normal bone and tooth structure, and are found especially in fish-liver oils, egg yolk, and milk or are produced in response to ultraviolet light

Medical Definition

vitamin D

noun

: any or all of several fat-soluble vitamins chemically related to steroids, essential for normal bone and tooth structure, and found especially in fish-liver oils, egg yolk, and milk or produced by activation (as by ultraviolet irradiation) of sterols: as

a

: calciferol

b

: cholecalciferol

called also sunshine vitamin