A predisposition toward developing certain allergic hypersensitivity reactions. Atopy may have a hereditary component, although contact with the allergen must occur before the hypersensitivity reaction can develop.

1923, from atopia (see atopy) + -ic.

allergic reaction (pop)

Having an inherited predisposition to allergies.

related to or caused by a hereditary predisposition toward developing allergic reactions

Of a hereditary predisposition towards developing hay fever and other allergic reactions. (i.e. "out of place")

Refers to a group of inherited diseases where there is often and inherited tendency to develop allergic conditions.