I guess now you have a sense of how jarring it can feel to some of us to be called "trans" in those moments when we are going about our day simply as a man or a woman — or as a person, never mind our gender — especially when the transgender-related details of our bodies, histories, ideas, etc. aren't anyone else's immediate business.

If it is relevant to a conversation whether someone is trans, then it is likely also relevant whether someone is cis (i.e., not trans). "Cis" is a neutral way to specify that someone is "not trans" in contexts where that detail is relevant.

If you never want to specify that you're not trans, I hope you have a similar policy of never pointing out that someone else is.

After all, from my perspective, people calling me "trans," or telling me whether I'm a man or woman according to their definition, amounts to "people who aren't me...tell[ing] me who I am." The category of "trans" isn't one I ever inherently wanted or asked for, nor did I choose that word to describe the category.

As long as people have reasons to assess, classify, or describe other people's genders in neutral terms, "cis" will be one of those terms. It serves a purpose, which is why people use it. If you read many examples of the word "cis" in context, its meaning will begin to make sense to you.

If you don't like a certain term and find it annoying, you can ask your "female friend" not to apply it to you personally — a request she should honor as your friend. But just because you don't find the term necessary for yourself personally, or just because you never heard it before and had to ask Google what it meant, doesn't mean the word serves no purpose for any person or any message in any context.

Mocking the word "cis" indirectly encourages one's audience not to listen to trans-inclusive statements or trans people generally, since many trans people and our allies use the word "cis."