ZZZ is not a word in the dictionary yet sh, ah, uh, and ow are, to name a few. I realize that we say "sh" to someone along with the other words. But we don't actually say zzz, its something we do. We do use the phrase "catching some zzz's," so why isn't it a word?

closed as off-topic by Jim, Drew, Kevin Workman, Edwin Ashworth, Nigel J Dec 22 '17 at 6:08

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