black cat vs fisher cat

black cat and fisher cat both are nouns.

Word	Noun	Adjective	Verb	Adverb
black cat	Yes	No	No	No
fisher cat	Yes	No	No	No

As nouns, black cat and fisher cat are synonyms defined as:

black cat and fisher cat: large dark brown North American arboreal carnivorous mammal

Other synonyms of black cat include fisher, Martes pennanti, pekan.

black cat (noun)	fisher cat (noun)
large dark brown North American arboreal carnivorous mammal	large dark brown North American arboreal carnivorous mammal