As a Cheesehead (born in Wisconsin, near Milwaukee) I've seen that spelling often.
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I was really surprised that it wasn't in Webster's Dictionary!
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It is in the Oxford Dictionary though. The definition pretty well tracks how I've seen the word used.
noun
informal
simplified spelling of night
grist for a million late-nite TV jokes
"nite". Oxford Dictionaries. April 2010. Oxford Dictionaries. April 2010. Oxford University Press. 11 November 2010 <
http://oxforddictionaries.com/view/...1271577>.Dan
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