Hindi-Urdu word काला kālā (i.e. black, dark) has its origin in a Proto-Dravidian word *kar- (black, to be burnt). The term was borrowed via Middle Indo-Aryan. Compare words for black in Tamil கருமை, Kannada ಕರಿಯ, Telugu kaggu (to be burnt) & Malayalam കരി. Old Indo-Aryan had Shyama श्याम, Asit असित, Tama तम etc for black / dark.