No problem, not a problem, not a big deal, no biggie, no worries, that's cool, it's cool, I'm cool with it. It is short for "ain't gonna be no thing". It means that everything is cool, and that there are no worries, no problems.

It can also be used as a general statement without prior posing of a question having expectation of an answer. For example, you may hear a coworker shout across the cubicles that he's going to change a part of the project you are working on, and you could just shout out "ain'go". In this case it would be a verbal confirmation that you heard him and are cool with it.
Ex. 1
Person 1: Hey, can you fix it?
Person 2: Yeah, sure, ain'go.

Ex. 2
Person 1: Hey man, doesn't that scare you?
Person 2: Ain'go.

Ex. 3
Person 1: I'm gettting tired of all this crap!
Person 2: Ain'go.
by acharney October 29, 2009
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