The users of "cis" usually claim that it is just an inoffensive, factual, objective, accurate, neutral word that harmlessly and ever-so-helpfully distinguishes between people who are not transgendered ("cis") and people who are transgendered (trans).
I do not accept that "cis" is these innocent harmless things because when someone labels another person as "cis", they are showing their support for the patriarchy-supporting political ideology of transgenderism, an ideology that is harmful to women and girls.
"Cis woman" and "cis lesbian" are important parts of the misogynistic and homophobic ideology of transgenderism. The "cis" prefix is deliberately used to further transgenderism's aim of relegating women to "cis women" and relegating lesbians to "cis lesbians", mere subsets of women and lesbians. Women is becoming a category that women must share with transwomen, whether women like it or not. Lesbian is becoming a category that lesbians must share with "trans lesbians" (i.e. transgender-identifying males who want sexual intercourse with females), whether lesbians like it or not.
For many years, transgender-identifying males have been called transwomen, which is a noun that recognises their specific life experience. Transgenderism has worked hard to bring about a subtle and seeming harmless but extremely significant change in word use - nowadays it is politically correct to use the term "trans women" where trans has become an adjective rather than part of a noun. This has been done to force people to accept the lie that transgender-identifying male people are just another type of women, like how "blonde", "talented", "rich", "poor", "fat", "thin", "old", "young", "British", "Japanese" etc. describe subsets of women. But it is a false comparison. The latter categories have actual women in them, because they are women who actually are those things. A transwoman is not any type of woman, not even a trans woman in the sense that they are not a biologically female person who is trans.
"Trans woman" is usually regarded as a description of a male person who feels they are a woman, but I think it is actually a more accurate description of a female person who feels that they are a man, which many people describe as a "transman". Likewise, "trans man" is a usually regarded as a description of a female person who feels they are a man, but I think it is actually a more accurate description of a male person who feels that they are a woman, which many people describe as a "transwoman".
BTW, I think it is also more accurate to describe a transwoman's so-called "neovagina" as a "neopenis" or "neoscrotum", but male doctors have decided that the removal of a male's penis and repurposing of a male's scrotum magically transforms male anatomy into female anatomy and therefore a pseudo female anatomical name for their creation has been invented.
All these words and distortions of their meanings are part of transgenderism's deliberate attempts at Orwellian redefinition of language that is designed to redefine illusion as reality, reality as illusion, lies as truth and truth as lies. This misogyny causes a relegation of women in patriarchy's gender hierarchy, and this is causing a reduction in the rights of women and girls.
I'm an adult human female. This traditional meaning of woman describes me and every other woman (the people with female biology) just fine thanks. Exclusion of male people from the category women is valid and justified because male people will always be male and can never be women. Nothing they can do will change that, so a redefinition of woman is not needed. There is already a word for adult people who are not women - it is not "transwomen" or "trans women", it is men. People who don't like the exclusion of male people from womanhood, can go argue with men to force men to be more accepting of other men.