The English language has a fantastic history, and over time, many words change meaning due to the new ways people tend to use those words. It's really quite fascinating and it's a large contributing factor to why I fell in love with English so deeply that I decided to major in it. However, sometimes English speakers use one word when they actually mean something else, and it has an unfortunate effect on the implications it has. The ones that bother me the most are when English speakers substitute the word stupid with something else. Have you ever heard someone do this? I am certain that you have. When I was in middle school, the common word that people would use instead of saying stupid was gay. Fortunately, I rarely hear that one anymore, but people still tend to use words that don't mean what they are trying to actually express.
The one that I continue to hear and have heard for years is retarded. I abhor the use of this word this way. Actually, any use of this word has become offensive and isn't used in the ways that it once was to describe people who are believed to have slower mental capacity than average. The fact is when someone chooses this word over stupid, dumb, bogus, or any other number of words, there are different and more harmful implications than many of those other choices.
My point is that we have gotten lazy with our speech. Instead of thinking about the negative implications of a word, we use what is deemed the easiest word to spit out by the people that surround us. Instead, we as English speakers should be aware that some words that are used in mainstream culture may have negative historical implications for those around us, even if we don't know it when we use it. There are some words in the English language that we shouldn't use anymore due to their negative past uses. I'm sure that you can think of a few words that aren't used very often due to increased awareness about how offensive they are to certain individuals or groups of people. Retarded is one of those words that we should not use. There are multitudes of other words that you can use instead of that highly charged word.
The next time you want to say that something is retarded, please reconsider. It's bad taste. It's offensive, and if that's not enough motivation, it hurts people around you. Perhaps your use of that word hurts people that you love and care about. English is a diverse language with a rich history so there is no reason that you absolutely have to use one offensive word instead of a different word with that makes the point you were trying to make, just without the negative connotations. Be aware of your speech; I'm sure there are certain words that you wouldn't like other people using, so maybe you should extend that same respect. Maybe you'll even expand your vocabulary by doing so.