allergen

noun

al·​ler·​gen ˈa-lər-jən How to pronounce allergen (audio)
: a substance (such as pollen) that induces allergy
allergenic adjective
allergenicity noun

Examples of allergen in a Sentence

common allergens, such as pollen
Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
In addition to dead skin and allergens, bacteria and fungus is also a concern. Kait Hanson, Southern Living, 22 Dec. 2025 And since the first line of treatment is to eliminate the allergen, Laura had a problem. Wendy Grossman Kantor, PEOPLE, 19 Dec. 2025 Earth-friendly materials like cotton typically promote airflow to keep hot sleepers comfortable and are ideal for those who are sensitive to certain allergens. Nashia Baker, Architectural Digest, 17 Dec. 2025 The issues include contamination risks, undeclared allergens, and potential bacterial exposure—all of which can pose health concerns. Jenna Anderson, Health, 16 Dec. 2025 See All Example Sentences for allergen

Word History

Etymology

borrowed from German Allergen,, blend of allerg- (in Allergie allergy) and -gen (in Antigen antigen)

Note: See note at allergy.

First Known Use

circa 1907, in the meaning defined above

Time Traveler
The first known use of allergen was circa 1907

Browse Nearby Words

Cite this Entry

“Allergen.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/allergen. Accessed 25 Dec. 2025.

Kids Definition

allergen

noun
al·​ler·​gen ˈal-ər-jən How to pronounce allergen (audio)
: a substance (as pollen) that causes allergy
allergenic adjective

Medical Definition

allergen

noun
al·​ler·​gen ˈal-ər-jən How to pronounce allergen (audio)
: a substance that induces allergy
inhaled allergens
a suspected food allergen

More from Merriam-Webster on allergen

Last Updated: - Updated example sentences
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