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
To forcefully insert.
by matthx January 31, 2006
by KarsaOrlong February 26, 2017