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7–dehydrocholesterol

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noun 7–de·hy·dro·cho·les·ter·ol \ˈsev-ən-(ˌ)dē-ˌhī-drō-kə-ˈles-tə-ˌrōl, -ˌrȯl\

Medical Definition of 7–dehydrocholesterol

: a crystalline steroid alcohol C₂₇H₄₃OH that occurs (as in the skin) chiefly in higher animals and humans and that yields vitamin D₃ on irradiation with ultraviolet light

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