- any substance capable of inducing an allergy
WordReference Random House Learner's Dictionary of American English © 2026
al•ler•gen /ˈælɚdʒən, -ˌdʒɛn/USA pronunciation
n. [countable]
WordReference Random House Unabridged Dictionary of American English © 2026- Immunologya substance that brings about an allergic reaction.
al•ler•gen
(al′ər jən, -jen′),USA pronunciation n. [Immunol.]
- Immunologyany substance, often a protein, that induces an allergy: common allergens include pollen, grasses, dust, and some medications.
- aller(gy) + -gen 1910–15
Collins Concise English Dictionary © HarperCollins Publishers::
allergen /ˈæləˌdʒɛn/, allergin /ˈæləˌdʒɪn/ n
'allergen' also found in these entries (note: many are not synonyms or translations):
desensitize
- dust mite
- hypersensitive
- reaction
- sensitivity
- sensitize
- allergenic
- allergy
- desensitization
- inhalant
- patch test
- scratch test