vitamin K

British  

noun

1. any of the fat-soluble vitamins, including phylloquinone and the menaquinones, which are essential for the normal clotting of blood

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vitamin K Scientific  

1. Any of a group of fat-soluble vitamins that are involved in the formation of prothrombin and other clotting factors in the liver and are essential for normal clotting of the blood. (The K is derived from the German word koagulation.) Vitamin K is also involved in bone formation and repair. Two forms occur naturally: vitamin K ₁, which is synthesized by plants, and vitamin K ₂, which is mainly synthesized by intestinal bacteria. The other forms are synthetic substances with similar chemical structures.

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Example Sentences

Delving deeper, the researchers conducted structural simulations and molecular docking studies to elucidate whether the vitamin K homolog interacts with mGluR1.

From Science Daily • Oct. 14, 2025

Ms Skinner told the inquest that vitamin K administration had been a "routine part of newborn care for many years".

From BBC • Oct. 27, 2023

For example, leafy greens with high amounts of vitamin K can lower the effectiveness of the blood thinner warfarin.

From Salon • Sep. 18, 2023

A diet rich in fruits and vegetables provides antioxidants, potassium, magnesium, vitamin K and vitamin C, each of which plays a role in bone health.

From Seattle Times • Sep. 4, 2023

After suctioning the mucus from my nostrils, she gave me a shot of vitamin K to coagulate my blood.

From "Middlesex: A Novel" by Jeffrey Eugenides