j-in 

Or variations like: J,Jay-in,J-en,J-in-it,Jayen Jayin or J-in-off,J-ed(past tense) sometimes be confused with names Jayne, Jay, Jade, or Jason. A derivative / abbreviation for the present tense phase "jacking off" or "jerking off", which is slang for masturbation. Similar to the abbreviations: HJ,BJ,FJ or ZJ. The letter "J" when used alone can be short for "Jizz" or seamen, or in proper context (along with J-ed) can be the past tense of "jacking off".

" Hey, sorry I did not answer I was totally j-in when you called'
" Yea, I had to bust out a quick safety J in the bathroom the flying J"
" I J-ed like six times last night"
" I got J all over her"
" I J-ed all over her"

j-in by Michael P. P. April 1, 2008

J in the Fay 

To glaze your partners face like a donut via ejaculation.

Did you j in the fay last night Joe? Yeah man her face was like a squirrel by the way she took my nut.

J in the Fay by gameovaries May 4, 2010

j in the b 

short hand for Jack in the Box aka jack in the crack

i got hella sick last night from eating j in the b

j in the b by bk 88 December 9, 2008

Sexy J'in

The act of makin out on the dance floor, at either a local drinking establishment or at a hall.

I went out to the local drinkery last night and i was sexy j'in hot broads all night long!

Sexy J'in by Chuck Biggs April 21, 2007

Dr. J in the ABA

A phrase used to describe the look of a woman's pubic hair when it's unshaven and resembles an afro.

"I was expecting a George Foreman but when I finally got her pants off, it was more like Dr. J in the ABA."

Dr. J in the ABA by Brenda Barger July 27, 2006

j'd in my p's

A shortening of the ever-popular catch phrase "I jizzed in my pants."

Korean #1: Hey I heard StarCraft 2 is coming out in late 2009.
Korean #2: Yeah, when Blizzard announced that, I j'd in my p's.

j'd in my p's by mastashih April 3, 2009

j.o'in

Masturbating, jerking off.

Billy was about to download some porn when he heard his buddy yell from outside, "hey would you quit j.o'in in there?"

j.o'in by Julius February 8, 2005