Once a boy meant a black servant. A slave. Didn`t you watch the final scene in Wild Wild West when two guys are hanging on a wheelchair high above the ground, one is black (Will Smith) and gets pissed off when the other calls him boy ???
If you are white, they read your boy as a derogatory expression.
However, when they say it to each other, it has a meaning of a guy, I suppose, in Polish - chłopie - chap, pal.
Thanks for the enlightenment,Pawian. I'll certainly steer clear of any slang I don't understand well.
