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

Liquid irritants, including chemicals, can also cause sharp pain in your eye. —Anna Giorgi, Verywell Health, 1 Aug. 2025

As a result, your scalp will come in contact with less irritants, which can help make wearing braids much more comfortable (and longer-lasting). —Essence, 16 July 2025

Adjective

Correspondent Scott Pelley anchored the report, which relied heavily on an interview with a leading Trump irritant — former top Hillary Clinton advisor Marc Elias. —Los Angeles Times, 4 July 2025

But where Daniel Tiger is a visual and auditory irritant, Peep’s world is delightfully quirky and genuinely funny, in no small part because Joan Cusak provides voice-over commentary. —Vulture Editors, Vulture, 23 July 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