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A phrase used when you think something is right but you really don't know jack shit.
Guy 1: Is my wife home from here business trip yet? I'm planning on bringin' some chicks over for a party.

Guy 2: I'm 99% sure she isn't.

Wife: I've been here all fucking day you asshole.
by Jay Danger April 24, 2008
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2
When you're sure but don't know for a fact
I'm 99% sure that's not what he meant
by Trisha1 December 17, 2017
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