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.
Pollen isn’t the only allergen impacted by climate change. Keerti Gopal, ArsTechnica, 8 May 2026 The first is to try to avoid the allergen by making changes in your home to reduce exposure. Levi Keller, The Conversation, 5 May 2026 If your pets go outside on high-pollen days, bathe them afterward — their fur carries allergens directly onto furniture and bedding. Allison Palmer, Sacbee.com, 30 Apr. 2026 Even feather dusters trap more dust and allergens than a paper towel. Mary Marlowe Leverette, The Spruce, 30 Apr. 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

Cite this Entry

“Allergen.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/allergen. Accessed 16 May. 2026.

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

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