It's Casual Friday to the next level, where people come to work without fixing their bed hair.
Joe: "Whoa, what's with your hair, dude? Rough night, last night?"

Bob: "Didn't you get the memo? It's Big Hair Friday!"

Joe: "Gee, I can't believe I forgot it's BHF!"
by GeekSquadRejects March 11, 2010
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