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 or vitamin D2 \-ˈdē-ˈtü\ : calciferol b or vitamin D3 \-ˈdē-ˈthrē\ : cholecalciferol
First Known Use of vitamin d
Medical Definition of vitamin D
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