> Note when I say black cab, I actually mean 黑车 whose direct English translation probably isn't very precise. Essentially, these are illegal taxis that would have wandered the streets looking for fares when they can get away with it. They don't mean a legal black livery car as in say...NYC.
It's just called that for historic reasons[1], referring to any illegal cab, usually which solicits people for rides. They don't have to be of the Romani people.
Gypsy cabs?