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.
Common allergens such as soy or nuts may be present in some varieties of plant proteins. — Anna Giorgi, Verywell Health, 3 July 2026 When children stopped eating peanuts, the allergens still found ways into their bodies. — Burkhard Bilger, New Yorker, 29 June 2026 The goal, proponents say, is to allow families to identify potential allergens. — Ben Szalinski, CBS News, 29 June 2026 Dogs who don't shed as heavily or who have different coat textures are often referred to as hypoallergenic, but there is no consistent evidence that these breeds produce fewer allergens. — Madeline Gunderson, USA Today, 2 July 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 7 Jul. 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

Nglish: Translation of allergen for Spanish Speakers

Britannica.com: Encyclopedia article about allergen

Last Updated: - Updated example sentences
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