I pretty much just thought of the name as a colloquialism. Lots of things get 'common' names that are inaccurate.Fishers are not cats, I have no idea why they call them fisher cats in some parts of the country, a fisher is a very large weasel/mink like animal it is very closely related to the pine marten only will grow much larger. They don't look like cats nor are they built like a cat, more like a cross between a weasel and a wolverine LOL.
Not only does not really resemble a 'cat', it also doesn't catch or eat 'fish'.
Here's some info on how it got to be called 'fisher cat'.
Despite the name fisher, the animal is not known to eat fish. The name comes from colonial Dutch fisse or visse due to its resemblance to the European polecat (Mustela putorius). In the French language, the pelt of a polecat is also called fiche or fichet.[4]