• synonyms


noun Pharmacology.
  1. a white, crystalline, water-soluble solid, C6H7N3O, used in the treatment of tuberculosis.
Show More

Origin of isoniazid

First recorded in 1950–55; short for isonicotinic acid hydrazide
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018

British Dictionary definitions for isoniazid


  1. a soluble colourless crystalline compound used to treat tuberculosis. Formula: C 6 H 7 N 3 O
Show More

Word Origin

C20 isoni (cotinic acid hydr) azid (e)
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

isoniazid in Medicine


  1. An antibacterial compound used in the treatment of tuberculosis.
Show More
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.