Formal:
* Feline
* Cat (This is the most common and neutral term)
Informal:
* Kitty
* Missy
* Mouser
* Pussycat
* Fifi (This one is a bit dated, but still used)
* Sissy
* Fluffy (Often used if the cat is long-haired)
Other options:
* Dam (This is a scientific term used to refer to a female animal that has given birth)
* Gill (This is a common term for a female cat in some parts of the world, especially in the UK)
It's important to note that some of these terms may be considered offensive or derogatory, so it's best to use them with caution.
Ultimately, the best term to use for a female cat will depend on your personal preference and the specific situation.