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

The law requires that food labels identify the food source of all major food allergens used to make the food. —Matthew Robinson, MSNBC Newsweek, 22 Aug. 2025

In July, artisan-style bread distributed to Walmart and Kroger stores was recalled for undeclared nut allergens due to a change in the product's packaging. —Karen Brewer Grossman, Southern Living, 11 Aug. 2025

Vanilla Bean cartons were accidentally filled with Cookies and Cream ice cream, which contains undeclared soy and wheat allergens. —Jenna Anderson, Health, 11 Aug. 2025

Some hotels venture away from these traditional pillows and offer down-alternative pillows made of recycled materials that are free of allergens. —Nashia Baker, Architectural Digest, 1 Aug. 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