This is why I got into the military habit of male and female. It's impossible to be wrong based on age. An infant female and a 99 y/o female are both still females.
Also, females I've noticed seem to say boys alot more often than men. For example, I've heard them often refer to boys night out, or the boys are partying. Same thing with girls night out and whatnot. Luckily I avoid the social context, but it can be confusing. Before I joined, I was corrected multiple times by women refering to themselves as girls (and they were in college) saying it made them feel old. I understand the wish by women to be young, because it is generally associated with beauty and sexuality, but seriously... it's also associated with the intelligence of a youngling as well, at least to me.
So I just use female, or the name. I have a habit of not using shortened names like Jen for Jennifer or Betsy for Elizabeth.
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I am Jon Stewart with some Colbert cynicism, Thomas Edison's curiousity, wrapped around a hardcore gamer sprinkled very liberally with Deadpool, and finished off with an almost Poison Ivy-esque love/hate relationship with humanity flourish.