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Definition of "mental retardation" [mental retardation]

  • Subnormal intellectual development as a result of congenital causes, brain injury, or disease and characterized by any of various cognitive deficiencies, including impaired learning, social, and vocational ability. Also called mental deficiency. (noun)

American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.