Jew

I agree that it's an offensive term. In England it has been used since Shakespeare's time to mean someone who is tight with their money. In the past it wasn't thought of by those who used it as being racially offensive (in fact, I have heard the word used twice in almost the same breath - once in an uncomplimentary way of a miserly person and again to describe the race of someone they actually admired! The person who uttered it was completely unaware of the incongruity of what they were saying.) I haven't ever come across it as a description of a cheat. That may be a Canadian usage. It comes from the long association of Jews with the banking industry in Europe and their reputation for being careful and meticulous. The only way to deal with the situation is not to show offence but, whenever possible, to try to educate the person (without being pedantic, of course). You are right that the people who use the word do so without any knowledge of (or real reference to) the Jewish people. For them, it's just a word but they should understand that it is uncomplimentary, pejorative and unjust and that, like the word 'fat', can be deeply offensive.