Which word is older, "okay" or "hallway"? How about "kibosh" or "string quartet"? Do you use the word "hello" correctly in your historical writing? I wrote an article about words that are newer than you thought (okay, than I thought) and words that are older than you'd (I'd) guess.
The article is over at Leah Braemel's blog. Go read it, comment and you can win an ebook. Go on! So far, your chances of winning are 100 percent!! (as in, no one's commented yet.)