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1.
The day out of the week where you wear your favorite flannel on Friday just to be awesome and good looking. It can be any kind of flannel. And it doesn't have to be the same one every wekk

It can also be called FFF for short.
"Hey dude, don't forget to wear your flannel for Fancy Flannel Friday this week! You forgot last week and you were the only one in class without one!"

"FFF is my favorite day out of the week! I get to wear my brand new flannel I just bought.
by DrummerJosh January 28, 2012