al·​ler·​gen | \ ˈa-lər-jən How to pronounce allergen (audio) \

Definition of allergen

: a substance (such as pollen) that induces allergy

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Other Words from allergen

allergenic \ ˌa-​lər-​ˈje-​nik How to pronounce allergenic (audio) \ adjective
allergenicity \ ˌa-​lər-​jə-​ˈni-​sə-​tē How to pronounce allergenicity (audio) \ noun

Examples of allergen in a Sentence

common allergens, such as pollen
Recent Examples on the Web Last fall, the Food and Drug Administration took its first steps toward changing labeling requirements to add sesame as an allergen. NBC News, "More than 1.5 million Americans could have a sesame allergy," 2 Aug. 2019 Roach dust, made of tiny bits that roaches shed from their bodies, is an allergen and can trigger or worsen asthma symptoms. Brian Resnick, Vox, "One big reason you can’t get rid of cockroaches," 3 July 2019 In some cases, marks on your body may be hives (also called urticaria), which is characterized by red, itchy bumps or welts that appear suddenly upon exposure to an allergen. Jenn Sinrich, SELF, "12 Common Face 'Bumps' and How to Deal With Them," 31 May 2019 Expect allergen-free dishes and gluten-free fish & chips as well as keto and paleo menu options. Michael Russell, oregonlive, "One of Portland’s best oyster bars is opening a seafood market, restaurant," 8 Nov. 2019 Try offering both allergen-free treats and regular candy. Melissa Gray, CNN, "Your guide to Halloween trick-or-treating etiquette," 31 Oct. 2019 Additionally, as it's equipped with a HEPA filter, owning a D7 will go a long way towards keeping your home allergen-free. Jonathan Chan, USA TODAY, "The best robot vacuums for pet hair of 2019," 16 Oct. 2019 According to the Environmental Protection Agency, the average American already spends about 90 percent of their time indoors, which is a shame, but also equals more time exposed to potential allergens in your home’s air. Paige Szmodis, Popular Mechanics, "Ward off Allergens With This Winix Air Purifier, 50% off on Amazon Today," 8 Oct. 2019 The deceased was not informed that there were allergens in the order. Claudia Harmata,, "Teenager Allergic to Dairy Died After Restaurant Said His Birthday Burger Was Safe to Eat: Coroner," 15 Sep. 2019

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

borrowed from German Allergen,, blend of allerg- (in Allergie allergy) and -gen (in Antigen antigen)

Note: See note at allergy.

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Time Traveler for allergen

Time Traveler

The first known use of allergen was circa 1907

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Statistics for allergen

Last Updated

7 Dec 2019

Cite this Entry

“Allergen.” The Dictionary, Merriam-Webster Inc., Accessed 16 December 2019.

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More Definitions for allergen


How to pronounce allergen (audio)

English Language Learners Definition of allergen

medical : a substance that causes an allergy


al·​ler·​gen | \ ˈa-lər-jən How to pronounce allergen (audio) \

Kids Definition of allergen

: a substance that causes an allergic reaction


al·​ler·​gen | \ ˈal-ər-jən How to pronounce allergen (audio) \

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

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