hay fever

from The American Heritage® Dictionary of the English Language, 5th Edition.

• noun An allergic condition affecting the mucous membranes of the upper respiratory tract and the eyes, most often characterized by nasal discharge, sneezing, and itchy, watery eyes and usually caused by an abnormal sensitivity to airborne pollen.

from The Century Dictionary.

• noun A feverish attack, coming on in the summer, with inflammation of the mucous membrane of the nose and eyes, or conjunctivitis, bronchitis, and asthma, and caused by the pollen of various plants, especially of the ragweed.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun An allergy to the pollen of grass or other plants that causes symptoms similar to those of a cold; pollinosis.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

• noun a seasonal rhinitis resulting from an allergic reaction to pollen