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1.
Green Beret Nap Time. Time during the work day used to recover from the previous night. Previous night's activities usually include excessive drinking and sexual contact with multiple women at late hours due to the rock star status of being a Green Beret, thus requiring GBNT the next day.

Only authorized for use by US Army Special Forces.
Last night was crazy, man. It's about noon, how about some GBNT?
by LongTabMed August 16, 2011