grain itch n an itching rash caused by the bite of a mite of the genus Pyemotes (P. ventricosus) that occurs chiefly on grain, straw, or straw products compare GROCER'S ITCH
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a self-limited eruption with wheals and itching, caused by the mite Pyemotes ventricosus, which parasitizes the larvae of insects that infest straw, grain, and other plants; it affects persons coming in contact with host plants. Called also acarodermatitis urticarioides and prairie or straw i.Medical dictionary. 2011.