I have done a lot of thinking about this lately, especially as it pertains to "appropriate" use. Mental Retardation is a medical term. It used to be an umbrella term for most all developmental delays. But it is being used less and less, which is probably a good thing. Just as saying "Crippled" was at one time the appropriate term, it is no longer. MR is quickly being replaced, even in the "appropriate" settings, for which I am exceedingly grateful.
For the time being, the noun is appropriate to use. It is a condition.
The adjective is not appropriate. Really, it has never been appropriate, but it's even less ok now than it once was. The only thing it does is apply limitations, particularly to what the individual is expected to be able to contribute to society. It's incredibly unfortunate.
As hurtful as it can be to those who hear the term used inappropriately, I really do feel bad for the people that use it without remorse. Because it usually means a few things. First of all, they have never had anyone around them brave enough to stand up and tell them that what they are doing is inappropriate and hurtful. Second, they have never had the privilege of knowing one of the beautiful wonderful people in this world who have been given this clinical diagnosis but who certainly make the world a better and brighter place for being in it. They really are missing out on some very important experiences in life. I only hope that their ignorance is a temporary state. In the meantime, I will continue my crusade to try and fix this.
Here is your little ministerial moment - Remember the directive to "love your neighbor as yourself"? Well, some people seem to have a really hard time with that one, for a variety of reasons (that I will probably address in the future). So when it comes to this, let's take it one step further. Try to love your neighbor as you would your own sibling or spouse or child. You may realize a few things about yourself and others!