irritant

1 of 2

noun

ir·​ri·​tant ˈir-ə-tənt 

: something that irritates or excites

irritant

2 of 2

adjective

: causing irritation

specifically : tending to produce physical irritation

Synonyms

Noun

• headache
• nuisance
• thorn
• frustration
• annoyance

Examples of irritant in a Sentence

Noun

dust and other lung irritants

The delay was a minor irritant.

Recent Examples on the Web

Noun

Reducing exposure to irritants like chlorine can be helpful there. —​wendy Wisner, Parents, 9 July 2025

Many have been peaceful, but some have resulted in clashes with law enforcement as officers made arrests and used chemical irritants to disperse crowds. —Khaleda Rahman shane Croucher, MSNBC Newsweek, 11 June 2025

Adjective

In Silicon Valley, however, regulators are often viewed with suspicion—at best an irritant, at worst the enemy. —Christiaan Hetzner, Fortune, 22 June 2025

Public broadcasting has been an irritant to conservatives for a long time. —Llewellyn King, Boston Herald, 10 May 2025

Word History

First Known Use

Noun

1802, in the meaning defined above

Adjective

1636, in the meaning defined above

Kids Definition

irritant

1 of 2 adjective

ir·​ri·​tant ˈir-ə-tənt 

: tending to produce anger, annoyance, impatience, soreness, or inflammation

especially : tending to produce physical irritation

irritant

2 of 2 noun

: something that irritates

Medical Definition

irritant

1 of 2 adjective

ir·​ri·​tant ˈir-ə-tənt 

: causing irritation

specifically : tending to produce inflammation

irritant

2 of 2 noun

: something that irritates or excites

specifically : an agent by which irritation is produced

a chemical irritant