If someone really, truly, genuinely believes that CIS is actually a thing someone can be, I have a challenge.
For every term you know is disputed, keep substituting for YOUR clearer definition to see if the meaning stays the same as you intend it.
For example, I would say:
I am a
I am an
I am an
...and so on
So perhaps your version might be:
I am a
I am a
I am a
I am a
I am a
at which point I have to ask, why we are redefining people in reference to those who are one anatomical type, yet persist in claiming to identify with an anatomy they do not possess? Anyway,
since to be of the sex class that produce ova, and to correctly identify oneself as such, factually equates to "I'm biologically female and know it "...
The whole definition of ciswoman ends up as
"I'm female, I know it, and I'm not male"
which pretty much sums up my entire objection to being shoehorned into a category with male people who call themselves, erroneously, 'women' so that they can pretend we have something in common and we're all just sub types of women..