SINCE 1828

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vitamin D

noun

Definition of vitamin D

: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 play \-ˈdē-ˈtü\ :calciferol

b or vitamin D₃ play \-ˈdē-ˈthrē\ :cholecalciferol

See vitamin D defined for kids

First Known Use of vitamin d

circa 1921

Medical Dictionary

vitamin D

noun

medical Definition of vitamin D

: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

Learn More about vitamin d

Britannica.com: Encyclopedia article about vitamin D

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