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Some stupid cunt thought that Marines were always saying "December Five" when they were actually saying "Semper Fi" which is the Marine Corps motto for "Always Faithful" This bitch asked the question on Yahoo so now Marines say "December Five" because it took off and is rather hilarious at how stupid this bitch was.

Shortened version is 12/5.
Marine 1 in a text message: "12/5"

Marine 2 in a text message: "12/5"
by GruntLife July 10, 2011
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