STD monday is the best day of the week in the army. On that day, you get to have sex with anyone you want (hint, STD). It's usually on a Monday and tons of babies are conceived with in that time frame.
Stacey: OMG, I had sex with Phil on STD Monday and now I'm pregnant!

Tara: You shoulda used protection. Now your gonna end up with an Army Brat.
by Shawty b u f f <3 June 24, 2011
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