E.F 

1) a child with a face like it has down syndrome.
2) one fugly ass bitch

dude1: "hey did you see that new down syndrome girl in our school?"
dude2: "oh yeah, E.F., right? shes supposed to be 'normal..'"
dude2: "yeah, okay, dude! lets go put her back in the hospital where she belongs!"

E.F by madison,nj+summit,nj=death September 30, 2009

E-f 

fundamentally, an electronic announcement of a boyfriend/girlfriend. phonetically, rhymes with 'bf'. usually referred to as in the context of a relationship status on a social networking site, i.e. facebook, myspace.

hey, did you hear about bree's new e-f?

yeah they've been going out for a while but she just changed her status on her facebook to in a relationship.

wow, they must be getting serious

E-f by DanielWebz July 22, 2009

E.F.A.

E.F.A., short for "Equality For All", is supposedly the world's first bestiality-rights organization.

She could be the president of E.F.A.

E.F.A. by Prickly Bear September 7, 2010

e:f,b

Edit: Fuck, beaten.

Some guy posts the same thing you wanted to, but did it first.

e:f,b by TheRochester April 3, 2003

E.F.P.

An acronym for the phrase "easy Freshman pussy". This is often used by high school Junior or Senior (sometimes even people who are graduated form high school) douche bags who are too insecure to bang girls their own age. Many reasons fuel the phenomenon of E.F.P., but it is most commonly because a 17 year-old penis looks gigantic to a 14 year-old.

Guy 1: "Damn, dude... She's kind of young."

Guy 2: "Shut the fuck up: you know I love me some E.F.P."

E.F.P. by Reefer_420_Madness October 28, 2012

E.F.S. 

Edited For Sarcasm:Used in internet forums, to convey an even harsher subtle form of sarcasm. Maybe directed at an individual or group when modifying a quote or story. Also acceptable, as an inside joke between users on the forum.

Example:
"ZOMG! The obligatory "OMG HALO" post! I'm so cooool anti-conformity FTW!!!"

When Edited for Sarcasm (E.F.S.)...

Result:
ZOMG! "OMG HALO" FTW!!!

E.F.S. by Ihatesoup May 27, 2007

e.f. or f.f? 

Eat first, or fuck first?

"C'mon, let's go to bed."

"e.f. or f.f?"

"both."

Alleged to be old Navy slang, meaning, "You wanna get some real food or some tail first?" Occurs in _Time Enough for Love_ by Robert Heinlein. When Dora, "The Adopted Daughter," propositions him, Lazarus asks her "E.F. or F.F.?" She answers, "Both," which is in character for her and also has multiple meanings.

e.f. or f.f? by s%mebody July 9, 2012