‘Pussy’ comes from the word ‘pusillanimous.’
Pusillanimous means, in short, to give little credence to important issues while, at the same time, making mountains out of mole hills. Some would define it as a lack of courage, but this definition is too simplistic and lacks a historical context. Pusillanimity can be seen as a lack of prioritization. One way or another, it has nothing whatsoever to do with ‘lady parts,’ nor does it denigrate anyone by comparing them to such. It denigrates them by other means.
“So powerful is the influence of fashion, it can even cause murder to be regarded as a venial peccadillo.” – Charles Mackay
If you’re so hell-bent on comparing someone to ‘lady parts,’ call them a cunt, instead.