This expression, meaning “diagonally opposite,” was formed from a misspelling in English of the French word quatre (“four”) prefixed to “corner.” Although the word has nothing to do with cats or kittens, in various dialects all three spellings are acceptable: “catty,” “cater” or “kitty.”
But unless you have somebody holding your golf clubs permanently stationed in the corner of your room, you shouldn’t use the spelling “caddy corner.”
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