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

However, high-dose biotin supplements could affect the results of vitamin D blood tests. —Jillian Kubala, Health, 27 Mar. 2025

The increase in sunlight boosts serotonin levels and vitamin D production, which enhances mood and energy levels. —Tribune Content Agency, Mercury News, 25 Mar. 2025

Most people can increase their vitamin D status by eating vitamin D-rich foods, getting safe sun exposure, and optimizing absorption. —Brittany Lubeck, Ms, Rdn, Verywell Health, 20 Mar. 2025

In particular, a joint study by Creighton University in Nebraska and the University of Miami, Florida, found that caffeine reduced the expression of vitamin D receptors on osteoblasts—the cells in our bodies responsible for producing bone. —Fiona Embleton, Glamour, 18 Mar. 2025

Word History

First Known Use

circa 1921, in the meaning defined above

Rhymes for vitamin D

• abc
• absentee
• addressee
• adoptee
• agouti
• allottee
• amphorae
• amputee
• apc
• apogee
• appointee
• assessee

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