Cambridge Dictionaries online Cambridge Dictionaries online

The most popular online dictionary and thesaurus for learners of English

  

allergen

noun [C]
 
 
/ˈæl.ə.dʒən/ US  /-ɚ-/ specialized

Definition

a substance that can cause an allergy (= condition of the body reacting badly to something) but is not harmful to most peoplePoisoning and allergy
(Definition of allergen noun from the Cambridge Advanced Learner's Dictionary & Thesaurus © Cambridge University Press)
Focus on the pronunciation of allergen