taken from the term "prod femmes" in pre-revolutionary france, meant that they were proud, wise, virtuous women. These days, it's more of a discriminatory word, stating that women could be "too" proper, too wise, and so on, especially when not interested in sex. It's also a word men *think* they can use in order to get women to perform sexual favors with them, and in order to put them down a notch - which in fact is absolute bullshit. The word prude may not seem like a good term, but it in fact is a compliment suggesting a lesser id and a higher intelligence and a stronger will and confidence than most.
"dude, she's a prude. she won't have sex with me, that bitch!".
"she's a dignified, respectable, uptight, classy, prudish woman, uninterested in sex, and for good reason - men are worms, (scum), and rabid animals obsessed with sex, not to mention there's aids to worry about and std's too. good for her/him."