moron

The feeble-minded may be divided into: (1) Those who are totally arrested before the age of three so that they show the attainment of a two-year-old child or less; these are the idiots. (2) Those so retarded that they become permanently arrested between the ages of three and seven; these are imbeciles. (3) Those so retarded that they become arrested between the ages of seven and twelve; these were formerly called feeble-minded, the same term that is applied to the whole group. We are now proposing to call them morons, this word being the Greek for "fool." The English word "fool" as formerly used describes exactly this grade of child--one who is deficient in judgment or sense. [Henry H. Goddard, in Journal of Proceedings and Addresses" of the National Education Association of the United States, July 1910]