An informal expression part ways with one person (usually a friend or co-worker) a good night after then end of an evening's festivities, usually uttered when the following day is a work day.
Harry: "Thanks for the ride home man, God I can't believe I gotta work in in 6 hours"

Albert: "Anytime man, was a good night out. Sleep fast, buddy!"
by Bigfatbino July 31, 2011
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