We often hear these words during an
election cycle. Each of these words has a different meaning. The
medical definitions have been mostly abandoned and the words are now
used more in a pejorative sense, rather than diagnostic.
In psychology, an idiot has the least intelligence on the IQ scale,
equivalent to someone who is mentally challenged. Idiot derives from
the ancient Greek, 'idio', meaning “person lacking professional
skill” or “mentally deficient person incapable of ordinary
reasoning.” Those who have an IQ between 0 and 25 are considered
idiots.
From Middle French imbécile, from Latin imbēcillus meaning weak or
feeble, literally “without a staff.” An imbecile is considered
equivalent to moderate retardation or moderately mentally
challenged. People with IQs between 26 and 50 are considered
imbeciles.
The word 'moron' was coined in 1910 by psychologist Henry H. Goddard
and derived from the ancient Greek word 'moros', which meant 'dull'.
Those who have an IQ between 51 and 70 are considered morons. A
moron is the highest level of intelligence for someone who is mildly
mentally challenged.
These terms were popular in psychology as associated with
intelligence on an IQ test until the 1960s. They were then replaced
with the terms mild retardation, moderate retardation, severe
retardation, and profound retardation. Other factors besides IQ are
now used in diagnosing these levels of mental deficiency.
Retarded comes from the Latin 'retardare', which means “to make
slow, delay, keep back, or hinder.” The term retarded was used to
replace the terms idiot, moron, and imbecile as these terms
gradually became thought of as derogatory. Now 'retarded' is
considered a derogatory term.
Many old words seem to pop up around election time as politicians
seek to differentiate themselves, while preaching the same drivel.
Even politician used to be a good word, which has now become
thought of as derogatory.