I wonder if it's considered less offensive among people who use etymologically similar words, like firemen (flame retardant) or biologists (to retard growth.)
It's less offensive among those who actually work with retarded people :-/
"Mentally challenged" type of insults seem to have their own cycles of use. Words like "idiot", "imbecile", or "cretin" used to be a clinical diagnosis, then stopped being medical terms, and nowadays are considered to if not mild then non-horrible.
I suppose that makes sense. Still raises my heart rate when I hear it, but that's my problem not the speaker's, and I'll defer to people with more experience on propriety.
If it's worth saying, but not worth its own post (even in Discussion), then it goes here.
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