from
The Collaborative International Dictionary of English v.0.48
Moron \Mo"ron\ (m[=o]"r[o^]n), n. [Gr. mw^ros foolish, stupid.]
1. (Pedagogy) A mentally retarded person whose intellectual
development proceeds normally up to about the eighth year
of age and is then arrested so that there is little or no
further development; an adult having the mental
development of an 8-to-12-year old. A moron is considered
capable of doing routine work under supervision.
[Webster 1913 Suppl. +PJC]
2. Hence, a very stupid person. [informal, derogatory]
[PJC] -- {mo*ron"ic} adj. -- {mo*ron"ic*al*ly} adv. --
{mo"ron*ism} n. -- {mo*ron"i*ty} n.