mental retardation

dated uncountable

(psychology, dated) A developmental disability in which the person has a very low intelligence quotient, usually below 70, plus difficulty in multiple areas of daily life. Evidence of this disability must have appeared before the person reached adulthood for diagnosis.

Japanese Meaning

知的障害：発達障害の一種で、知能指数が通常70以下であり、日常生活の複数の領域において適応行動に困難を示す状態。診断は成人に達する前にその特徴が認められることが条件となる。