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English definition of “allergy”

allergy

noun [C]  /ˈæl·ər·dʒi/ us  
a condition that causes illness when someone eats certain foods or touches or breathes in certain substances: Your rash is caused by an allergy to peanuts.
allergic
adjective  /əˈlɜr·dʒɪk/ us  
I’m allergic to cats.
(Definition of allergy from the Cambridge Academic Content Dictionary © Cambridge University Press)
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