What is the origin and meaning of the word 'moron'?

Moron was originally a scientific term, coined around 1912 by psychologist Henry Goddard from a Greek word meaning "dull" or "foolish", and used on the English version of the "Binet Scale" of human intelligence. The Binet Scale was developed in the early 1900's by Alfred Binet, a French psychologist and inventor of the first usable intelligence test, the basis of today's IQ test. The Binet Scale went approximately as follows:

Normal ----- IQ 85-115
Deficient ---- IQ 71-84
Moron ------ IQ 51-70
Imbecile ---- IQ 26-50
Idiot -------- IQ 0-25
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The word moron was coined in 1910 by psychologist Henry H. Goddard to describe a mentally retarded person with a mental age between 8 and 12 or an IQ in the range of 51-70. The word is derived from the Greek "moros", meaning dull. +4

Armonteutmaronne- also known as a moron. A french twit who gets owned on every post "it" places on FF.

Moron was originally a scientific term, coined by psychologist Henry Goddard from a Greek word meaning "foolish" and used to describe a person with a genetically determined mental age between 8 and 12 on the Binet scale. It was also once applied to people with an IQ of 51-70 and was a step up from "imbecile" (IQ of 26-50) and two steps up from "idiot" (IQ of 0-25). The word moron, along with "retarded" and "feeble-minded" (among others), was once considered a valid descriptor in the psychological community, though these words have all now passed into common slang use, exclusively in a detrimental context.

In his later years, Goddard recanted all his previous writings, but they had already been translated and published, including in German. They were a heavy inspiration for the Nazis who sent people deemed "morons" to the gas chambers first (Source: BBC Documentary "Stupidity").

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