白痴

Noun

 * 1) idiot; halfwit
 * 2) idiocy; intellectual disability

Etymology 1
From.

Noun

 * 1) idiocy, imbecility
 * 2)  profound mental retardation, indicating an IQ of under 25
 * 3) an idiot, an imbecile
 * 4)  a person suffering from profound mental retardation, with an IQ of under 25

Usage notes

 * No longer used in the clinical sense, much as English is no longer used clinically.