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

Subsequent investigation indicates the problem was caused by an exceptional combination of circumstances in which the ERP (Enterprise Resource Planning) did not include the allergen on the packaging. —Anna Commander, MSNBC Newsweek, 11 Aug. 2025

The incorrect packaging does not list wheat and soy ingredients on the product label or alert consumers to the allergens. —Karen Brewer Grossman, Southern Living, 11 Aug. 2025

These products help maintain healthy environments by regulating moisture and airflow, reducing allergens, and improving overall comfort. —Joe Cornell, Forbes.com, 7 Aug. 2025

The most common fruit allergens are banana, peach, and kiwi.22 IBS: As discussed above, certain fruits can trigger symptoms for people with IBS. —Sohaib Imtiaz, Verywell Health, 30 July 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