I don't know who needs to hear this but words don't refer to things in the physical world because there are no "things" in the physical world. Words refer to abstractions. That doesn't mean they're not useful but if you try to treat language like mathematics this will bite you in the ass real quick.
Mathematics don't work so well because they match reality perfectly, they work because we have created them from whole cloth with complete disregard for reality. Even basic geometric shapes are an impossibility in the physical world. The entirety of physical sciences are built on leaky abstractions we have found to offer predictive power, not perfect truths.
The universe is soup and we have to define the chunks into existence to make sense of it. Words mean what we agree on them meaning and this changes over time and that's fine. There's nothing special about "biological sex" and there's no reason to pretend gender has to give it any more than a passing glance when talking about society. Definitions are fuzzy, heuristics are king, truth is ultimately unknowable.
#TransRightsAreHumanRights #WhatIsAWoman #TERF #Semantics