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definitions

menadione

[men-uh-dahy-ohn]
noun Pharmacology.
  1. a synthetic yellow crystalline powder, C11H8O2, insoluble in water, used as a vitamin K supplement.

Origin of menadione

First recorded in 1940–45; me(thyl) + na(phthalene) + di-1 + -one
Also called vitamin K3.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for menadione

menadione

noun
  1. a yellow crystalline compound used in fungicides and as an additive to animal feeds. Formula: C 11 H 8 O 2Also: vitamin K 3

Word Origin for menadione

C20: from me (thyl) + na (phtha) + di- 1 + -one
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
menadione in Medicine

menadione

[mĕn′ə-dī′ōn′]
n.
  1. A synthetic vitamin K derivative occurring as a yellow crystalline powder and used as a vitamin K supplement.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.