Is a hyena a feline?

Hyenas are neither canine nor feline. They belong to their own family, the Hyaenidae, which includes the three species of hyena (spotted, striped and brown), and their relative, the aardwolf. The Hyaenidae family is placed on the Feliformia (cat-like) branch of the order Carnivora, along with the families Felidae (cats), Viverridae (civets) and Herpestidae (mongooses). Hyenas are therefore more closely related to cats than to dogs, since the dog family, Canidae, is placed on the Caniformia (dog-like) branch of the order Carnivora, together with the families Mustelidae (weasels), Procyonidae (raccoons), Ursidae (bears), Otariidae (eared seals), and Phocidae (true seals). The dog-like appearance of hyenas is due to convergent evolution - the process by which different species evolve similar solutions to similar problems.
While Hyenas are not technically felines, they are classified as being feliformia meaning "cat-like". Hyenas are classified this why because they have double chambered auditory bullae, which means that the bony capsule containing the inner and middle ear is double layered rather than single layered as is the case with caniforms. Feliforms also tend to have fewer teeth, shorter snouts, specialized cranassials (the premolars used to shear flesh), and retractable or semi-retractable claws.