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.
When exposed, the body produces an antibody known as Immunoglobulin E (IgE), which binds to the allergen and triggers immune cells to release histamine and other chemicals. New Atlas, 3 July 2025 Prime subscribers can also score savings on household essentials, like a best-selling Levoit air purifier, which tackles airborne allergens and pollutants, plus a cordless vacuum that doubles as a handheld to clean above-ground messes. Clara McMahon, People.com, 2 July 2025 Rugs, upholstered furniture, and antiques should be thoroughly cleaned or professionally treated to remove dirt, allergens, and any unwelcome critters. Brandee Gruener, Southern Living, 29 June 2025 This helps capture fine particles and allergens—sometimes up to 99.99%—for an incredibly thorough clean. Nashia Baker, Architectural Digest, 26 June 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 11 Jul. 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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