vitamin D

American  

noun

1. any of the several fat-soluble, antirachitic vitamins D 1 , D 2 , D 3 , occurring in milk and fish-liver oils, especially cod and halibut, or obtained by irradiating provitamin D with ultraviolet light, essential for the formation of normal bones and teeth.

---

vitamin D British  

noun

1. any of the fat-soluble vitamins, including calciferol and cholecalciferol, occurring in fish-liver oils (esp cod-liver oil), milk, butter, and eggs: used in the treatment of rickets and osteomalacia

---

vitamin D Scientific  

1. Any of a group of fat-soluble sterols necessary for normal bone growth, especially vitamin D ₂ (ergocalciferol) and vitamin D ₃ (cholecalciferol). Vitamin D is found in milk, fish, and eggs and can be produced in the skin on exposure to sunlight. A deficiency of vitamin D in the diet causes rickets in children.

---

Etymology

Origin of vitamin D

First recorded in 1920–25

Example Sentences

See Examples For:

vitamin D

Insufficient calcium intake and low vitamin D can limit the body’s ability to build and maintain strong bones.

From Science Daily ● Jun. 25, 2026

The study adds important evidence to an area that has received relatively limited attention and offers a better understanding of year-round vitamin D risk among vulnerable populations.

From Science Daily ● Jun. 24, 2026

The findings challenge the widely held belief that spending time in the summer sun is enough to restore healthy vitamin D levels.

From Science Daily ● Jun. 24, 2026

"I was on high doses of vitamin C, vitamin D, turmeric, a special de-bloat supplement and I would regularly drink water with electrolytes in," Ginger explains.

From BBC ● Jun. 20, 2026

He needed vitamin D for the boy or he was going to get rickets.

From "The Road" by Cormac McCarthy