Chomu chornogo i bilogo nosoriziv nazivayut chornym i bilim

The names of black and white rhinos are misleading – as both are actually grey. The white rhino is said to have gotten its name from the Afrikaans word for wide (‘wyd’), referring to its wide, square lip (in contrast, black rhinos have a pointy upper lip). Early English explorers mistook this word for ‘white’ and consequently named this species ‘white’ rhino, and the other ‘black’ rhino to differentiate.

National Geographic