The definition of an allergy is a sensitivity to a specific substance which causes a negative bodily reaction, such as sneezing, wheezing, itching or difficulty breathing.(noun)
Breaking out in hives when getting stung by a bee is an example of an allergy.
See allergy in Webster's New World College Dictionary
noun pl. allergies
Origin: Ger allergie < Gr allos, other (see else) + -ergeia, as in energeia (see energy)
See allergy in American Heritage Dictionary 4
noun pl. al·ler·gies
Origin: German Allergie
Origin: : Greek allos, other; see allo-
Origin: + Greek ergon, action; see werg- in Indo-European roots.
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