Where do you draw the line in using terms with proper-name origins in an alternate world setting?
I recall the anecdote about a Ravenloft author inventing the term "air moss" because "Spanish moss" was right out. This past week's word-of-the-day list includes terms referring to characters in Dickens. While a child-training thief like Gaedren Lamm from Pathfinder's Curse of the Crimson Throne might be perfectly described as a "fagin," you couldn't actually use that term without throwing every English major in the audience.
Sometimes the call isn't so obvious. It's all right to use "mesmerized," isn't it? "Hypnotized" sounds even goofier in an alternate world fantasy, but the former term has a guy's name in it. On the other hand, "Damascus steel" is right out.
What are some real-world terms that you'd think twice about using in an alternate world setting? And what are some that you think are questionable but okay?