n. pl. al·ler·gies
1. A condition in which exposure to a substance, such as pollen, latex, animal dander, or a particular food or drug, causes an overreaction by the immune system that results in symptoms such as sneezing, itching, rash, and difficulty breathing or swallowing.
2. Informal An adverse sentiment; antipathy: an allergy to cocktail parties.
[German Allergie : Greek allos, other; see ALLO- + Greek ergon, action; see werg- in the Appendix of Indo-European roots.]
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