Will asked me to post about "words that make [me] see red." He noted that the use of the word "retarded" as an insult is one to which he is extremely sensitive. Unfortunately, tons of people use this term without really remembering that it of course refers to a group of people with a disability who could be hurt by the use of the term as an insult. I would recommend a general rule of thumb that if a word refers to the immutable characteristic of a class of people, it should never ever be used as an insult. Thus, we should eradicate "that's so retarded," "that's so gay," or "you throw like a girl" from our vocabularies. Instead we can say, "what a total asshat," "how tacky," or "you clumsy dork."
That having been said, I guess I don't really "see red" with regard to particular terms. I lived through college during the early 90s when campus speech codes were all the rage, and I retain a lively suspicion of the idea of regulating speech or professing extreme outrage at particular turns of phrase. While I would certainly be offended at the use of hostile racial or sexual epithets (the "n" word comes to mind), I generally assume in most instances that people who use particular offensive terms or expressions don't mean anything malicious by it and simply haven't thought it through.
Here are some expressions that I hear regularly, that grate on me but which I don't necessarily hold against the speaker:
"You throw like a girl." OK this one does kind of piss me off, but when this came up with my in-laws, I honestly don't think it had occurred to any of them WHY it would be wrong to use this expression. In their minds, it's just an immutable given, or perhaps a funny joke, that girls can't throw. (See my post on this here.)
"Pardon the expression, but he really jewed me down." Actually, this one pisses me off too. When the speaker says "pardon the expression," that shows he or she KNOWS it's wrong and is fully aware that the expression is dissing a whole class of people. What's so hard about saying, "He drove a hard bargain" or "He was cheap?" I always call people on this one.
"Oriental." (to refer to people from Asia or people of Asian descent). This one is like nails on a chalkboard to me, and I hear it all the time. I actually grew up using this term without viewing it as derogatory, and I sincerely doubt that most people who use it have any malicious intent. But when you think about it, it defines a whole continent of people in terms of its geographic location in relation to "the West." The term also connotes a sort of degenerate luxury and exoticism. Why not just say "Asian" or "Asian-American?"
"She's a slut." I hear this used most frequently by teenage girls to describe other girls whom they perceive as overly sexually active. There is something incredibly demeaning about defining someone's entire worth as a person in terms of their sexual choices. Naturally, this kind of judgment is directed most often at the female half of the species.
"Your girl." This one's bizarre. At my last firm, I was friendly with a secretary who would regularly use this term. She would say "Is your girl in today?" The first time she said this, I had no idea what she was talking about. It emerged that she was referring to my secretary. It made it sound like I was a slave owner or something. Yuck.
The term "girl" to refer to an adult woman. This one's tricky. I was indoctrinated at Mount Holyoke never to use the word "girl" to refer to a woman over the age of 18. I have to admit that it did seem stilted at first to use the word "woman" to refer to my 18 year old pal down the hall. I suppose "girl" could be considered to be the colloquial equivalent of the word "guy," and thus appropriate at any age, but to me "girl" does imply extreme youth. I find it grating that women models are always referred to as "girls" in the fashion industry. I also had a weird conversation with a cop who kept referring to a "girl at the Attorney General's Office" whose name he couldn't remember. I was shocked when it emerged that he was referring to a 45-year-old battle-worn trial veteran, because I had pictured a sweet young thing right out of school. Sometimes, and maybe this is my imagination, it seems as though men in our culture can't quite bring themselves to use the word "woman." They'll say "girl," "female" or "lady," but never woman. You can tell me that I'm crazy if you'd like, but it's almost as though many men see the word as either slightly insulting or overly sexual. I will give the conservative Christians a big hand on this -- I find it refreshing that they will routinely use the word "woman." (Of course, their actual view of women is another story.)
Last but not least: "Panties." There is nothing offensive about this word, but boy does it give me the heeby-jeebies. I will never ever ever say the word "panties." Ever. It sounds so cutesy and dimunitive. "Underwear" or "underpants" seems a bit more dignified. "Knickers" (used in England) is okay, but it would sound unnatural for an American to talk about knickers and plus it sounds like you're talking about men's cropped golf pants from the '20s. Fortunately, I don't have much occasion to talk about panties anyway.