Short for "Jealous as fuck" or "Jelly as fuck", used in instant messenger and other online social media websites. The word is used to show your jealously of what your friend has got or is doing.
Friend 1: hey man I got the new call of duty game 3 days early!
Friend 2: really?? dude i'm sooo JAF!!
Friend 2: really?? dude i'm sooo JAF!!
by minispecs123 September 14, 2011
Get the JAFmug. Just A Friend Syndrome
-When a good friend likes, you but doesn't like you the way you do.
- The syndrome where you can never get a boy/girl-friend because you're too good friends.
-When a good friend likes, you but doesn't like you the way you do.
- The syndrome where you can never get a boy/girl-friend because you're too good friends.
John- *Megan turned me down, urgh, JAFS sucks.*
Rob- *Dude, you shouldn't have been such good friends*
Rob- *Dude, you shouldn't have been such good friends*
by martin188888 May 15, 2008
Get the JAFSmug. 
A person who stalks a wordbills50000/word on the internet because he is jealous he didn't get anywhere near wordMandy Moore/word. A wordplaya hatah/word.
by William August 16, 2003
Get the JAf'mug. 