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.
Neither allergen is listed on the packaging. Annabelle Canela, Parents, 15 Sep. 2025 Per Healthline, nuts are a top allergen in the United States that affects about 20 million people. Raven Brunner, PEOPLE, 14 Sep. 2025 Most thrift stores won't accept them due to concerns about bedbugs, allergens, and general hygiene. Nafeesah Allen, Better Homes & Gardens, 12 Sep. 2025 The Girl Scouts announced the new flavor on social media, where some fans expressed disappointment that the cookies contain allergens. Deirdre Bardolf, FOXNews.com, 12 Sep. 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 16 Sep. 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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