A “banner day” would be any time which one would want to celebrate, or would mean a time where everything went perfectly!
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What does "banner day" mean?
I believe it is the same thing as “red-letter day” which means a gooooood day, an exemplary day, stellar day etc…Source(s): My homeschoooled vocabulary 😛
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they make me feel ashamed. I am ashamed to be an American! It is b/c too many reasons to say on here.