- anything that irritates.
- Physiology, Pathology. a biological, chemical, or physical agent that stimulates a characteristic function or elicits a response, especially an inflammatory response.
Origin of irritant
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
Examples from the Web for irritant
An even smaller minority goes and returns so frequently that these lines can be an irritant.This Be Madness! America’s Outrageously Long and Totally Unacceptable Customs Lines
June 21, 2013
Tonic, irritant, and caustic; dose internally, one to two drachms.
Irritant, cathartic, stimulant, and antiseptic; one to one and a half pounds.
Narcotic, anti-spasmodic, and irritant poison; one to two drachms.
It is used externally as an irritant or vesicant to the skin.Poisons: Their Effects and Detection
Alexander Wynter Blyth
He must seize what is tickling him, putting his hand rapidly to the irritant.Montessori Elementary Materials
- causing irritation; irritating
- something irritant
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
Word Origin and History for irritant
1630s, from Latin irritantem (nominative irritans), present participle of irritare (see irritate). As a noun, from 1802.
Online Etymology Dictionary, © 2010 Douglas Harper
- Causing irritation, especially physical irritation.
- A source of irritation.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.