Female is part of the meaning of woman, not all of it, so they are not circular.

A 10 year old girl is female, but not a woman because she is not an adult. A full grown mother dog is female, but not a woman because she is not human.

If you're asking why woman has to include female, that gets into social convention (all words are made up and all definitions can change). That's what I meant when I said any definition is "circular," although I think the benefit of the doubt should go to whoever is using the traditionally understood meaning, because the purpose of language is to communicate.

Anyway, the distinction I'm drawing is that the AHF definition consists of three objectively verifiable traits. If you are missing any of those traits you are not a woman. If you have all three, you are a woman, regardless of anything else about you. This makes woman a useful term that can distinguish people from others in many different contexts.

The trans definition of woman is "a person who sees themselves as a woman." They would LIKE it to mean "a person who accepts the gender role traditionally associated with the female biological s*x," but this excludes women who are perfectly happy to look or act mannish, as well as many trains who self identify as women do not wish to adopt that traditional gender role. It also does not account for anyone who personally wishes they were the opposite s*x/gender, but considers that impossible and does not adopt a trans identity.

So the TERF definition is "a person with these traits" while the definition is "a person who accepts this term." One definition is much more objective and useful than the other.

Their are female birds, plants, and plug ends. There are no woman version of these things