[graeme]

I read up on "retard" due to this post. Retard was originally used to replace words such as cretin, imbecile, fool, etc.

Those were once clinical terms, but by the late 19th century they had become pejorative. So retardation was introduced, and worked for a while. Then it became a schoolyard insult, and was replaced by mentally disabled or mentally challenged.

If schoolchildren invent an insult out of "disabled", then I imagine a new term will be introduced. This doesn't mean it wasn't a good idea to replace "retarded", but it seems likely that there's no permanent solution.

[cameronh90]

They already have, sort of. I have heard "what, are you challenged?" or "you are special" a few times now... which is actually one step further than disabled down the euphemism treadmill.

[graeme]

Yeah, special was already an insult when I was in school in the 90s. Didn't realize challenged had become one already. Have they made a noun out of it or just an adjective? Retarded produced both, which is one probably helped it spread.

[mvaliente2001]

And that's one of the problems with PC. In that regards, it doesn't work. If we call "orange thinkers" those which IQ is around or above average and "green thinkers" to the other group, then sooner you'll hear "What? Are you a green thinker?"

[Cushman]

But I know for a fact that "retarded" and "retardation" have not been replaced; they're being phased out for political reasons, but the terms still have a specific meaning and are definitely still in use clinically.

What I doubt (lacking real evidence) is that the person-noun form "retard" -- think about phrases like "discharging a retard", "managing retard behavior", "a unit full of retards" -- was ever in widespread clinical use, as "idiot" or "imbecile" were in the past. The move to stop using those terms was not about just changing the word, but also recognizing mental disorders as something distinct from a person's inherent nature.

(Again, similar to the move from "negroes" to "black people". Either can be used pejoratively, but the former is arguably intrinsically offensive.)