A damaging immune response by the body to a substance, especially pollen, fur, a particular food, or dust, to which it has become hypersensitive
an allergy to feathers
Allergy to a foodstuff; an instance of this; (in later use also) an adverse reaction to a particular food attributed to allergic mechanisms.
A condition involving a wide range of symptoms thought to be caused by sensitivity to the chemical substances encountered in the modern environment. Its medical characterization is controversial