Gorgonops itself was a medium to large-sized representative of the group, with a skull length of twenty to thirty-five centimetres, depending on the species. It ranged from 2 to 2.5 metres long from nose to tail. Gorgonops derived superior speed from long legs held beneath its body.
The holotype of the type species, Gorgonops torvus, was in 1876 one of the first therapsids described, by Richard Owen, who also coined the name "Dinosauria" on the basis of the first known dinosaur fossils. It was also used as the type for which Richard Lydekker described the family in 1890. Five years later, in 1895, Harry Govier Seeley used this genus to establish the group as a whole. In later years, a large number of further species and genera were designated, but some of these turned out to be synonyms.