Some people say/think that the obvious answer is a dog. Others might say/think it's a mouse but astonishingly the truth is that the opposite of a cat is a monkey.
The Opposite of Cat is Dead Cat.
There isn't really an opposite but when i think of the opposite i think of cat.
Cat
The opposite of cat is usually considered to be dog.
It means a wild cat. Opposite of domestic cat(:
Cat
dog
'tac'
Of your cat is good with the opposite species, then a dog
A cat
The opposite of a bobtail cat, which is characterized by its short tail, would be a cat with a long, full tail. Breeds like the Maine Coon or the Siamese are examples of cats known for their long tails. In terms of behavior, an opposite might also refer to a cat that is more independent compared to the typically affectionate nature of many bobtail breeds.
The opposite gender of a fox (male) is a vixen(female).
The opposite of an adventurer is a couch-potato.