Poliomyelitis: Inflammation of the gray matter of the spinal cord. P., acute anterior, acute inflammation of the anterior horns of the gray matter of the spinal cord, leading to a destruction of the large multipolar cells of these horns. It is most common in children, coming on during the period of the first dentition and producing a paralysis of certain muscle groups or of an entire limb.

Gould’s Illustrated Medical Dictionary, 1895

Poliomyelitis: An inflammatory process involving the gray matter of the cord. Acute anterior p., inflammation of the anterior cornua of the spinal cord; an acute infectious disease caused by the poliomyelitis virus and marked by fever, pains, and gastroenteric disturbances, followed by a flaccid paralysis of one or more muscular groups, and later by atrophy.

Stedman’s Medical Dictionary, 1995