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2.
Any day that a lot of people at youtr school or know are acting like bitches for no reason or there mad at someone.
"Shut up loser". Wow I think today must be bitch day!
by the myth the man the legend April 26, 2010
 
1.
Falls on November 15th; a day for all women to celebrate their youth and naughtiness.
Bitch day is right around the corner, ladies!
by vioguevara15 November 04, 2013