a congenital disorder characterized by short stature, hypertrophy of one side of the body, and elevated urinary gonadotropin hormones without precocious sexual maturity. Motor development is often delayed because of muscle weakness. Physical features include pseudohydrocephalus, a condition of normal head circumference but a small face, giving the appearance of an enlarged head. Various studies have found a higher than average incidence of intellectual disability among people with this disorder. Also called Silver’s syndrome. [Henry K. Silver (1918–1991), U.S. pediatrician; Alexander Russell (1914–2003), British pathologist]