massive powerful herbivorous odd-toed ungulate of southeast Asia and Africa having very thick skin and one or two horns on the snout
"The massive rhino stood silently in the African savanna, its thick skin protecting it while its single horn scanned for danger."
A rhinoceros.
"After years of working hard, he finally turned his rhinos into a comfortable retirement fund."
money
The word rhino is simply a shortened version of rhinoceros. It entered English as an informal clipping to make the long scientific name easier to say and write.