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

In addition to being high in creatine, herring is packed with other important nutrients, including protein, vitamin D, iodine, selenium, and vitamin B12. — Jillian Kubala, HEALTH, 15 Sep. 2026

Health Benefits of Seafood Seafood is not only a nutritious protein source but also a source of vitamin D and heart-healthy omega-3 fatty acids. — Angela Ryan Lee, Verywell Health, 10 Sep. 2026

Low vitamin D is often a culprit when someone feels sluggish and fatigued. — Helen Carefoot, Flow Space, 10 Sep. 2026

Patchen studies how omega-3 fatty acids and vitamin D — another nutrient that fish is rich in — are associated with better lung function and lower risk of chronic obstructive pulmonary disease and emphysema. — Diana Anos, CNN Money, 4 Sep. 2026

Word History

First Known Use

circa 1921, in the meaning defined above

Rhymes for vitamin D

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

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