When someone lives in a penthouse suite, folks assume they've "arrived," both socially and economically. After all, the penthouse is at the top of the building. Its occupants can literally look down their noses at the little people. Both Britannica Online and Merriam-Webster define penthouse as "a structure or dwelling built on the roof of a building." Thanks guys, but we kind of already knew that. Digging a bit deeper, we found this explanation from Mavens' Word of the Day: "Penthouse" comes from the word pentis, which comes from apentis, which comes from apendere, which means to hang against or attach. (Still with us?) A pentis was a shed with a sloping roof attached to a wall or building. At some point (we don't know the exact date), people began referring to the structure's roof as a "pentis," and the actual shed became a "penthouse." Sheds? Sloping roofs? These definitions don't exactly make penthouses sound very swanky. So the next time a person tries to impress you by mentioning their new penthouse, you can politely ask, "That would be your shed attached to the wall?" Of course, you probably won't be invited to the penthouse-warming party. ref: http://ask.yahoo.com/20060220.html