allergy
n. a condition in which the body produces an abnormal or inappropriate immune response to certain, normally harmless substances known as allergens, such as dust, pollen, nuts, or animal dander. In an allergic person, the allergens stimulate the release of histamine and other chemicals, leading to symptoms that can include (but are not limited to) inflammation, sneezing, itching, and vomiting. See also anaphylaxis. —allergic
adj.