I've had a hunch for a while that the term gentleman is showing signs of disappearing from the language. Notice that in most public places the doors to rest rooms (that's toilets for those not prone to euphemism) are generally labeled ladies and men. The bloviating blowhards in our legislative bodies still persist in addressing one another as "the honorable gentleman from -----" and I'm not getting into the honorable part here and even refer to female colleagues as "gentlewomen." It all comes off as phony-baloney. In fact, the terms ladies and gentlemen, men and women, boys and girls haven't been used as consistent pairs for quite some time. Scott Fitzgerald wrote about men and girls at parties, and to call a group of grown-up females girls or gals is a sure way to ruffle feathers, while males don't seem to mind being called boys or guys. We seem to have more gender terms than we need in English.