al·ler·gen | \ˈa-lər-jən \

Definition of allergen 

: a substance (such as pollen) that induces allergy

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Other Words from allergen

allergenic \ˌa-lər-ˈje-nik \ adjective
allergenicity \ˌa-lər-jə-ˈni-sə-tē \ noun

Examples of allergen in a Sentence

common allergens, such as pollen

Recent Examples on the Web

Like many food allergens, the Ara proteins make up a high proportion of their plant, dissolve in water and resist digestion. Amber Dance, Washington Post, "Peanut allergy is one of the most severe food allergies. New therapies might help.," 12 May 2018 This Car Plug-In Air Purifier boosts your vehicle’s air quality, zapping foul odors and filtering out irritating allergens like dust and pollen — without producing any kind of scent to mask it. Taylor A Puskaric, USA TODAY, "5 Car Gadgets Every Roadtripper Needs," 4 Apr. 2018 Tate & Tate co-owner George Tate says the dish didn't include gluten, and there are signs around the business warning that the kitchen processes foods that contain nuts, wheat and other allergens. Mary Mooney,, "Suit: Oregon caterer's meal caused child's allergic reaction," 23 May 2018 The sauce has oyster extract, a shellfish allergen. David J. Neal, miamiherald, "This spice packet in this recalled food could be a problem if you have a food allergy," 13 June 2018 No cat is truly free of allergens, which are found not just on skin but also in saliva and urine. Kim Campbell Thornton, sacbee, "Cats’ quirks? Read about breeds," 27 June 2018 The most common indoor allergens are dust mites, pets and molds. Jamie Gold,, "Clearing the indoor air," 28 June 2018 Research shows that unlike typical allergic reactions that occur within a half-hour of exposure to an allergen, alpha-gal reactions can take three to six hours to manifest. Thomas Leavy, CBS News, "Maine on the lookout for ticks that cause red-meat allergy," 25 June 2018 Nothing tamps down the allergens that live in their fur and on their skin than a good cleansing. Dr. Patty Khuly, miamiherald, "Allergic to your furry friends? Here are tips to help manage pet allergies," 31 May 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'allergen.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of allergen

circa 1907, in the meaning defined above

History and Etymology for allergen

International Scientific Vocabulary allergy + -gen

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Statistics for allergen

Last Updated

12 Oct 2018

Look-up Popularity

Time Traveler for allergen

The first known use of allergen was circa 1907

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More Definitions for allergen



English Language Learners Definition of allergen

medical : a substance that causes an allergy


al·ler·gen | \ˈa-lər-jən \

Kids Definition of allergen

: a substance that causes an allergic reaction


al·ler·gen | \ˈal-ər-jən \

Medical Definition of allergen 

: a substance that induces allergy inhaled allergens a suspected food allergen

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More from Merriam-Webster on allergen

Spanish Central: Translation of allergen

Nglish: Translation of allergen for Spanish Speakers

Britannica English: Translation of allergen for Arabic Speakers Encyclopedia article about allergen

Comments on allergen

What made you want to look up allergen? Please tell us where you read or heard it (including the quote, if possible).


exaggeratedly or childishly emotional

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