An absurd hash tag greeting on twitter meaning "Happy follow friday", used by twitter junkies to tweet to long lists of followers on Fridays, usually clogging up everyone else's twitter feeds with tweets of no substance.
Horny4u: Happy #FF
SherlockHolmes411: Dude, that's the 50th tweet I've gotten from you today.
by CJ Ragsdale September 13, 2013
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