Catercornered

 "Our table was a long one in the corner catercornered from the bar." (from The Golden Box, by Frances Crane)

I was surprised when I came across Crane's usage of this word, because it was totally unfamiliar to me. Here in South Logan County we would say "cattycornered."

On the Grammarist website, I found two more options: kittycornered and caddycornered. Which of these you use is entirely a matter of regional preference. However:

"The term was originally catty-corner, which comes from the French word quatre, meaning four. When English speakers got their paws on quatre, it became cater, used to showcase the four spots on a die or the four legs of a beast. Or, in this case, the corners of four city blocks meeting. Eventually, cater-cornered became a term for something positioned diagonally from something else, like the opposite corners on a square die. Then, cater-cornered got clipped to catty-corner, kitty-corner and caddy-corner."