Zoologically speaking, the term panther is synonymous with leopard. The name leopard comes from Greek words for lion (leo) and panther (pardos). Panther and leopard are names for the same kind of animals, but panther is most often used for the black phase of the spotted leopard. The term black panther, therefore, refers only to the black leopard - a melanistic variant of spotted leopards.
For many years, it was thought that the leopard and panther were different species of cats, however, by the 20th century, scientists had confirmed that the leopard and panther belong to the same species. It is common to see a female leopard give birth to a mixed litter with a black cub along with a couple of fair spotted cubs as siblings. Black cubs grow into black leopards (black panthers) and fair cubs grow into fair spotted leopards. A black leopard can have black or light-colored leopards as parents.