A highly infectious viral disease that chiefly affects children and, in its acute forms, causes inflammation of motor neurons of the spinal cord and brainstem, leading to paralysis, muscular atrophy, and often deformity. Through vaccination, the disease is preventable. Also called infantile paralysis, polio.
[Greek polios, gray (since it affects the gray matter); see pel-1 in the Appendix of Indo-European roots + MYELITIS.]
po′li·o·my′e·litic (-lĭtĭk) adj.
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