vitamin K


Definition of vitamin K

1 : either of two naturally occurring fat-soluble vitamins C31H46O2 and C41H56O2 essential for the clotting of blood because of their role in the production of prothrombin

called also respectively vitamin K1\ -​ˈkā-​ˈwən How to pronounce vitamin K (audio) \, vitamin K2\ -​ˈkā-​ˈtü How to pronounce vitamin K (audio) \

2 : any of several synthetic compounds closely related chemically to natural vitamins K1 and K2 and of similar biological activity

Examples of vitamin K in a Sentence

Recent Examples on the Web Miso is rich in vitamin K, says Iu, which helps blood clot. Alyssa Jung, Good Housekeeping, "5 Incredible Health Benefits of Miso," 13 Sep. 2020 In Herbal Dynamics Beauty Vitamin K and Green Tea Brightening Eye Cream, vitamin K is the real star of the show. Nikhita Mahtani, CNN Underscored, "Want to fight dark circles? Look for these ingredients in your next eye cream," 21 Aug. 2020 The fresh arugula topping provides a boost of vitamin K, which can help lower blood pressure, maintain strong bones, and keep memory sharp. Woman's Day Kitchen, Woman's Day, "Mushroom and Arugula Salad Pizza," 28 May 2020 Radicchio provides a nice dose of vitamin K. Aside from playing a crucial role in blood clotting, studies suggest food sources of vitamin K promotes bone health. Darlene Zimmerman, Detroit Free Press, "In 17 years of writing recipes, I'd never used this ingredient — until now," 30 July 2020 Avocado oil provides a good source of B vitamins, vitamin C, vitamin E, vitamin K, folate, potassium, and fiber. Katlyn Moncada, Better Homes & Gardens, "Avocado Oil is the Versatile Pantry Staple You Should Be Using," 29 July 2020 For example, vitamin K will reduce the ability of blood thinners to work. Lisa Drayer, CNN, "Should you take a dietary supplement to prevent disease?," 24 June 2020 Protecting your bones: Cauliflower is abundant in vitamin K, which is required for both bone-mineral density and blood clotting. Stefani Sassos, Ms, Rdn, Cso, Good Housekeeping, "Is Cauliflower Healthy? All the Nutritional Facts and Benefits to Know," 12 Mar. 2020 Celery’s vitamin K helps blood to clot and protects bone density. Cynthia Sass, Mph,, "Health Benefits of Celery," 12 Dec. 2019

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'vitamin K.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of vitamin K

circa 1935, in the meaning defined at sense 1

History and Etymology for vitamin K

from the initial letter of Danish & Swedish koagulation coagulation, Norwegian koagulasjon & German Koagulation

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Time Traveler for vitamin K

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The first known use of vitamin K was circa 1935

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Statistics for vitamin K

Last Updated

23 Sep 2020

Cite this Entry

“Vitamin K.” Dictionary, Merriam-Webster, Accessed 24 Sep. 2020.

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More Definitions for vitamin K

vitamin K


Medical Definition of vitamin K

1 : either of two naturally occurring fat-soluble vitamins that are essential for the clotting of blood because of their role in the production of prothrombin in the liver and that are used in preventing and treating hypoprothrombinemia and hemorrhage:
a : a yellow oily naphthoquinone C31H46O2 that is obtained especially from alfalfa or made synthetically and that has a fast, potent, and prolonged biological effect, is effective orally, and is useful especially in treating hypoprothrombinemia induced by anticoagulant drugs

called also phylloquinone, phytonadione, vitamin K1

— see mephyton
b : a pale yellow crystalline naphthoquinone C41H56O2 that is obtained especially from putrefied fish meal and is synthesized by various bacteria (as in the intestines of humans and higher animals) and that is much more unsaturated than vitamin K1 and slightly less active biologically

called also menaquinone, vitamin K2

2 : any of several synthetic compounds that are closely related chemically to vitamins K1 and K2 but are simpler in structure and that have similar biological activity especially : menadione

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