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.
The Luxury Pillow keeps your head and neck in the ideal position to stay asleep all night, made with soft bamboo viscose material that naturally repels common household non-living allergens. — ABC News, 24 Oct. 2026 WinCo initiated the recall after the bread manufacturer, United States Bakery, determined the hoagie roll packaging did not declare the inclusion of sesame flour on the ingredient list and allergen statement. — Anne Ewbank, Sacbee.com, 23 Oct. 2026 Major allergens must be declared even when tucked inside a flavor blend. — Lauren Schuster, Fort Worth Star-Telegram, 21 Oct. 2026 Food businesses must take allergen risks seriously, every time. — Latoya Gayle, PEOPLE, 9 Oct. 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 27 Oct. 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

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