Ethnic- I hate how it's used as a lazy way to categorize everyone who isn't white. Can't be bothered to separate the Pakistani and Nigerian foods at your supermarket? Stick it all in the "ethnic" aisle.
Skinny - Stuck at the beginning of any low fat food. Makes it sound like "food for anorexic people" in my opinion
Aspie- Tries to make a serious medical condition sound like a cute club. I'm sure calling schizophrenics "schizies" wouldn't go down so well.
Afro-Caribbean - Used to lump two very different cultures which are separated by 4,000 miles and 400 years into one group just because they all have the same colour skin. It makes as much sense as putting American and Russian students in the same club just because Americans came from Europe 300 years ago.
Cancer - Used by the media to inspire terror among the masses. Want to sell more papers? Print an article containing statistics from Dr Cowboy that proves breathing causes cancer.
Diet - Used to mean a temporary unorthodox change to one's food intake in an attempt to lose weight. If we all just went back to the old meaning of "diet" which is what you normally eat in your lifetime then people might learn to eat better. You don't go on a diet, you change your diet. The former implies a short term fix to a long term problem.
Dating - Creates an illusion of structure and process to something that isn't structured or processed at all. Talking about dates is pointless because everybody has a different idea of what costitiutes a date. To some people "dates" don't even exist at all.
Shy - used to mean "anyone quiet". Shy implies that you are scared of people why are you assuming that I am scared/socially awkward just because I have nothing much to say?