FF means many things, some already said, I might (most likely will) repeat.
#1. Fist fucking- the act of stuffing a fist up a pussy *owch*
#2. Foot fucking- a type of masturbation that women do to their male partners dick.
#3. Final fantasy- a game played by geeks, such as my boyfriend, that I should probably learn to play.
#4. Fan Fiction- a type of writing that uses already made characters from books and movies and such that have sex, also called slash... gay LOTR ones at www.libraryofmoria.com.
#5. Father fucker- a person who likes to fuck their dad/friend's dad.
#6. Fucking freak- ... me...
I think I've made myself clear.
by MizMilenko May 28, 2004
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heres all the definitions for FF:

freindly fire
Fire fight
Flying fuck
Flaming Fist
Frostfire
fortissimo
focus fire
Front Wheel Drive
Forum faggot
Freedom Fries
finds funny
False Friend
Fake fuck
Foot Fucker
Fucking Fool
Fan Fiction
Final Fantasy
Front flip
fun fuck
Fucking freak
Father fucker
Fist fucking
Fat Fuck
Freshly fucked
Fatal Fury
Final Fight
Front Engine
Bob: FF!
Joe: False Friend?
bob: no
Joe: Fire fight?
bob: NO
joe: Forum faggot?
Bob: No, noob
Joe: Front flip?
Bob: wait it was the second one...
by Is this name used? August 7, 2006
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ff is texting short term for "fucking funny." Much more hip than an lol!
That girl is so ff. She makes me laugh my ass off!
by notnicole November 28, 2011
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"What you been doin? You look all ff."
by Speed Racer June 5, 2004
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"ff" is a term used to define what kind of porn you're going to find in the link it gives you. "ff" refers to female on female action. get ready for the lesbians!
Whoa! This story says it has "FF" in it! LESBIAN ACTION!
by lemonlime December 8, 2004
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This is the only definition of ff that matters for the purposes to this dictionary:

adj.

1. freshly fucked, as in a way of describing a big, ratty, messed-up hair-do that looks as if its wearer just got plowed something fierce in the back seat of a Chrysler LeBaron. Especially popular in the 80s and early 90s, the ff look is making a bit of a comeback today. Technically, one can be a virgin and still sport the ff look.

2. short for 'the ff look', or 'the freshly-fucked look'.
Sandy came out of the hair salon wearing the ff look.
by loveboat March 28, 2007
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