infantile paralysis

American Heritage® Dictionary of the English Language, Fourth Edition

1. n. See poliomyelitis.

GNU Webster's 1913

1. (Med.) An acute viral disease, affecting almost exclusively infants and young adults, characterized by inflammation of the anterior horns of the gray substance of the spinal cord. It is attended with febrile symptoms, motor paralysis, and muscular atrophy, often producing permanent deformities. Called also acute anterior poliomyelitis, poliomyelitis and polio. It is caused by any one of three polioviruses, and by the end of the twentieth century had been almost completely eradicated in developed countries by a widespread campaign of immunization.

WordNet 3.0

1. n. an acute viral disease marked by inflammation of nerve cells of the brain stem and spinal cord