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

In fact, the brand follows the National Eczema Association’s ingredient guidelines to avoid irritants and allergens. —Conçetta Ciarlo, Vogue, 26 June 2025

This may mean limiting your exposure to a range of irritants and allergens. —Mark Gurarie, Health, 22 June 2025

Adjective

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

The perp then sprayed the mother in the face and arm with the irritant as the train approached the Court Square-23rd St. station. —Nicholas Williams, New York Daily News, 21 June 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