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

Lifestyle factors: Smoking and vitamin D deficiency are associated with a higher likelihood of developing IBS.2021 A Quick Review Irritable bowel syndrome (IBS) is a functional gastrointestinal disorder that causes abdominal pain and changes in bowel movements. —Lindsay Curtis, Health, 15 Dec. 2024

Treatment is available for SAD and includes medications, vitamin D supplements, talk therapy, and light therapy. —Lana Barhum, Verywell Health, 4 Dec. 2024

Sufficient levels of vitamin D — which can be found in some foods like milk and fish, as well as sunlight — can boost the body’s ability to absorb calcium and improve bone health, according to the clinic. —Angelica Stabile, Fox News, 1 Oct. 2024

Sunlight through a window won’t have the same effect– glass reduces absorption of the UV rays needed for vitamin D production. —Jianying Zhang, Discover Magazine, 8 Nov. 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