Are Ferrets a type of Rodent

I note they are from the Mustelidae family which is said to originate at the same time as Rodents. But I also not that this Mustelidae family was a catchall family for mammals.

Why does this mean exactly? Are Ferrets totally different from other rodents, or are they very closely related? Are Ferrets as closely related to Rodents as say, Rabbits are?

Ferrets are not rodents. Rodents have no canine teeth. Ferrets rely on their well developed canine teeth to kill prey, mostly rodents, for food. Ferrets belong to the mammalian order Carnivora, or meat eating mammals. There are two great groups within Carnivora, the Caniformia (dog-like carnivores) and the Feliformia (cat-like mammals). The family Mustelidae include weasels, badgers, otters, minks, fisher, wolverine and ferrets. Mustelidae is part of Caniformia, which makes the ferret a dog-like carnivore.

Mustelidae is NOT a catchall family for mammals. The relationships among the mammalian orders is still largely unresolved. For example, there is a hypothesis that rodents are most closely related to rabbits, but the molecular evidence that support such a relationship is not robust. The bootstrap value for the node supporting a rodent-rabbit (lagomorph) relationship is very low, but some people embrace it nevertheless. The carnivores are probably most closely related to the hoofed mammals like horses, rhinods, cows, pigs, and to the whales, but not as closely related to elephants, dugongs, rodents, bats or the primates.

Ferrets are mustelids which are carnivores more closely related to cats and dogs than to rodents. The Mustellidae is by no means a catchall family. It is a monophyletic group composed of ferrets, weasels, the polecat, the pine martin, the fisher, the otters, the badgers, the meerkat, the mongooses, skunks, the wolverine, the fossa, and perhaps a few other members.

Ferrets are a rodent closer to the rat family