The grey parrot (Psittacus erithacus), also known as the Congo grey parrot, Congo African grey parrot or African grey parrot, is an Old World parrot in the family Psittacidae. The Timneh parrot (Psittacus timneh) once was identified as a subspecies of the grey parrot, but has since been elevated to a full species. The grey parrot was formally described in 1758 by the Swedish naturalist Carl Linnaeus in the tenth edition of his Systema Naturae. He placed it with all the other parrots in the genus Psittacus and coined the binomial name Psittacus erithacus. Linnaeus erroneously specified the type locality as "Guinea": the locality was later designated as Ghana in West Africa. The genus name is Latin for "parrot". The specific epithet erithacus is Latin and is derived from the Ancient Greek εριθακος (erithakos) for an unknown bird that was said to mimic human sounds, perhaps the black redstart. The species is monotypic: no subspecies are recognised. The Timneh parrot was formerly treated as a subspecies of the grey parrot but is now considered to be a separate species based mainly on the results from a genetic and morphological study published in 2007. Although Linnaeus placed all the parrots known to him in the genus Psittacus, only the grey parrot and the Timneh parrot are now assigned to this genus. The grey parrot is a medium-sized, predominantly grey, black-billed parrot. Its typical weight is , with an approximate length of , and a wingspan of . The grey colour on the head and wings is generally darker than its body. The head and body feathers have slight white edges. The tail feathers are red. Due to selection by parrot breeders, some grey parrots are partly or completely red. Both sexes appear similar. The colouration of juveniles is similar to that of adults, but typically their eyes are dark grey to black, in comparison to the yellow irises around dark pupils of the adult birds, and their undertail coverts are tinged with grey. Adults weigh .