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 of irritant

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

For many of us, these little irritants make screen-cleaning an easy chore to remember. — Kate Van Pelt, The Spruce, 23 Aug. 2026

Sharks are known to rub against reefs, sand, rocks and even the seafloor to remove irritants. — Melissa Cristina Márquez, Forbes.com, 28 July 2026

Adjective

China’s persistent reliance on food imports is a likely irritant to Xi, especially given recent global economic disruptions. — Caitlin Welsh, Foreign Affairs, 11 Aug. 2026

According to Jim McHale, president of JP McHale Pest Management, salt can act as an irritant or contact killer for pests with soft exoskeletons. — Olivia McIntosh, Martha Stewart, 6 June 2026

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