A bum, crackhead, homeless person, fiend for for drugs, or begger.
This is a true story: My cousin who works at McDonald's in Camden, NJ, was on his break. He went into the bathroom and he told me there was a geedy in there sniffing cocaine off the sink. My cousin told him to get out, but the geedy just looked up at him with the "practice your hard face in the mirror" look. So then, my cousin brushed the geedy's cocaine in the sink and rinsed it down the drain. The geedy stood up all tall, and ice grilled my cousin, so he ice grilled him back. Then my cousin opened the door, and the geedy started to walk out, but my cousin pushed him out. Then, 2 other geedies came out of the stalls, looking at my cousin like they were going to roll on him. Then my cousin said, "hold up, I'll be back". He went and got a steak knife from the kitchen, came back to the bathroom where the geedies were, and said,"Yall better get out, or I'mma stab the shit outta one of you geedies!" Then they left.