John Green tells us the history of some words you never wondered about in the latest mental_floss video. We now know what Carl Linneaus was thinking when he named the animal “lemurs,” but it's kind of creepy to think about. But there you go. The word Jumbo was a proper name before it meant "large." You'll get a kick out of what "senator" really means. What? You have to make a death pledge to buy a house? Some of these forty stories are pretty strange!