1) Trippin', acting erratically or inappropriately.
or
2) Having fun, or messing around.
1) My parole office is usually cool, but he started illin' when I told him I was back to shooting heroin and pimpin' hos.

2) Me and my boys was just sitting around illin'...
by buddhablaze January 28, 2003
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to be acting lame.

usually a pretty dope person acting totally whack.

something a hater does.
Dirty Dan: BababaBiyatch, hows it crackin baby bizzle?
Charisse: Shut the fuck up; you be illin' douche packer.
by Ambassador-C May 24, 2008
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Shaniqua was illin' me for dressin better than her.
by Aramel November 17, 2008
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You know the moon isnt green are you illin!?!?
by Soledad July 24, 2003
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A word used to describe something that is both "sick" (amazing) and "chilling" (relaxed). Synonomous with "epic" and "legendary" although with a somewhat more relaxed connotaion.
Yo brosif, that headshot was straight illin like a villain yo!
by CandyMan77 March 26, 2009
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Something pirates and theives and beastie boys do well and often.
"Most illinest b-boy - I got that feeling
I am most ill and I'm rhymin' and stealin'

by jim December 21, 2005
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