What is the feminine noun of cat?

Answer 1

The English language doesn't use masculine or feminine words. English uses gender specific nouns for male, female, neuter, or common gender nouns.

The gender specific noun for a male cat is "tom" or "tomcat".
The gender specific noun for a female is "cat" or "queen".

The noun "cat" is also a common gender noun for a male or a female feline.

Answer 2

There are no feminine nouns in English. All English nouns, even those that denote specifically male or female creatures, are of common gender. That said, cat and kitten are often used to refer to women in certain circumstances.