No. It's not. A female is a member of any animal species, not just humans, whose body is set up to produce large gametes. In mammals, except in the case of the platypus, females will carry the developing young of their species inside their bodies and give birth to them.

This can be observed objectively. And the external genitalia indicate whether somebody is male of female with roughly 99.98% accuracy. The alternative is a definition that depends on how somebody tells you they feel in that moment. It's so stupid, I can't believe we're even talking about it as if it's a serious conundrum.

Yes, there are rare occasions where due to some illness or birth defect, a female's body isn't actually be able to accomplish the task her body was set up to do. But this doesn't stop her from being a female. Any more than a person with any other birth defect is no longer a human.

If we know what a lioness is, I don't understand why we're pretending we don't know what a woman is.