allergen

noun

al·​ler·​gen ˈa-lər-jən How to pronounce allergen (audio)
: a substance (such as pollen) that induces allergy
allergenic
ˌa-lər-ˈje-nik How to pronounce allergen (audio)
adjective
allergenicity
ˌa-lər-jə-ˈni-sə-tē How to pronounce allergen (audio)
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.
Harrison added that the recall has nothing to do with an allergen, microorganism or pathogen contamination. — Saleen Martin, USA Today, 31 Aug. 2026 Clean-label positioning, allergen-free status, and single-source complete proteins sit at the intersection of sports nutrition, functional food, and the wellness side of beauty. — Tanya Akim, Forbes.com, 28 Aug. 2026 Experts recommend washing your duvet cover every week in hot water (130°F or higher) to kill allergens, dust mites, and bacteria. — Nafeesah Allen, Better Homes & Gardens, 19 Aug. 2026 That means scanning a 2D barcode can link you to an instruction manual, food allergens, coupons, show you what farm the product came from and whether the package is recyclable. — David Goldman, CNN Money, 18 Aug. 2026 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

Allen wrench
allergen
allergic
See all Nearby Words

Cite this Entry

“Allergen.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/allergen. Accessed 1 Sep. 2026.

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Kids Definition

allergen

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

Britannica.com: Encyclopedia article about allergen

Last Updated: - Updated example sentences
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