@HeartyBeast I like what you say : both definitions are interesting. Please notice the one based on self-identification is quite in fashion since 5 or 10 years but like all fashions it should subside a bit in the coming years, I mean at least in the western world (i think). When (if) this happens, the definition based on phenotypes will be seen as more important …it’s not just important for medical application : this is an oversimplification (of course).
P.S. : in response to your comment :
spoilerI’m offended because it is so daft. If I had to define a man and a woman, I would say that it is currently difficult as there are two definitions, one being based on biological sex (which is itself a surprisingly ticklish concept) and the other based around gender and self identification. Personally, I’m happy with the latter. The former is useful in medical contexts.