And I guess that's the problem. People who assume a TERFy definition of _woman_—like, say, the authors of the Merriam–Webster dictionary [("noun, **1.a.**, an adult female person")](https://www.merriam-webster.com/dictionary/woman)—generally aren't trying to invalidate anyone's "gender"; they're trying to talk about _biological sex_ using simple, universally-understood words. Biological sex is obviously not the only category in the world: in a lot of situations, you might care more about whether someone has living children—or for that matter, whether an organism is yellow—than what sex it is.
And I guess that's the problem. People who assume a TERFy definition of _woman_—like, say, the authors of the Merriam–Webster dictionary [("noun, **1.a.**, an adult female person")](https://www.merriam-webster.com/dictionary/woman)—generally aren't trying to invalidate anyone's "gender"; they're trying to talk about _biological sex_ using simple, universally-understood words. Biological sex is obviously not the only category in the world: in a lot of situations, you might care more about whether someone has living children—or for that matter, whether an organism is yellow—than what sex it is.