lesion le·sion (lē'zhən)
A wound or an injury.
A localized pathological change in a bodily organ or tissue.
An infected or diseased patch of skin.
in physiology, a structural or biochemical change in an organ or tissue produced by disease processes or a wound. The alteration may be associated with particular symptoms of a disease, as when a gastric ulcer produces stomach pain, or it may take place without producing symptoms, as in the early stages of cancer. Certain lesions, such as the genital chancre of syphilis, are diagnostic of a particular disease, and early recognition of the physical or biochemical injury can help to prevent later, more serious manifestations of a disease; thus, the recognition and classification of disease lesions is a major part of pathology.
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