allergen

noun

al·​ler·​gen ˈa-lər-jən 

: a substance (such as pollen) that induces allergy

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

Also, be aware of other potential allergens, such as dairy, eggs, soy, and nuts. —Ayesha Gulzar, Verywell Health, 8 Sep. 2025

Foster has been with the team for over a decade, and leads nutritional data and allergen safety for all food options on the Blacksburg campus. —Abigail Wilt, Southern Living, 8 Sep. 2025

This easy-to-use kit screens for over 120 common pet allergens—from food ingredients like chicken and wheat to environmental triggers like pollen and mold. —Kasey Caminiti, USA Today, 6 Sep. 2025

The company claims this delivers over a 99.99% bacteria removal rate and allergen reduction rate, all verified by the German technical inspection standards body TÜV SÜD. —Benny Har-Even, Forbes.com, 5 Sep. 2025

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

Kids Definition

allergen

noun

al·​ler·​gen ˈal-ər-jən 

: a substance (as pollen) that causes allergy

allergenic

ˌal-ər-ˈjen-ik 

adjective

Medical Definition

allergen

noun

al·​ler·​gen ˈal-ər-jən 

: a substance that induces allergy

inhaled allergens

a suspected food allergen