[petercooper]

So like how "lame" used to mean crippled or physically disabled but now generally doesn't in an informal context?

[shkkmo]

Except for "lame" in a formal context is still a relevant term.

I can't remember the last time I heard "retarded" used with the intention of referring to a developmentally disabled kids. Whenever I do hear that usage, I do point out to those people that the term when used that way is offensive and they should stop using it that way.