[Wintamute]

Well, "handicapped" means having a condition that hampers your ability to function optimally, whereas "retarded" means backwards, mentally less advanced, stupid. "Retarded" is very obviously the more pejorative term. Personally I avoid using the term "retarded" because of the extremely negative/unpleasant connotations surrounding the use of the term "retard" in our culture. I know that by invoking either of those words I could make people with handicapped loved ones feel uncomfortable. Yes for now the full choice of my vocabulary is curtailed, but it's called consideration, and it makes you and the people around you feel good. In the meantime there's plenty of other enjoyable/juicy/harmless words to use for something you want to criticise.

[quesera]

"Retarded" means slowed, or delayed. The antonym is "advanced". You can retard progress, development, rotation, etc.

It has only become a pejorative term because it's a label with negative connotations when applied to people. "Handicapped" is identical in this way.

Even if you're not sensitive to peoples' feelings about words, one good reason not to use "retarded" is that it makes you sound like a playground bully.

[Wintamute]

I was concentrating on the pejorative use of the term as relating to criticism of people and/or things. I think its obviously fine to say, for example, "the rotation of the wheel was retarded due to friction".

> Even if you're not sensitive to peoples' feelings about words, one good reason not to use "retarded" is that it makes you sound like a playground bully.

In not wanting to sound like a playground bully aren't exhibiting sensitivity to peoples' feelings?