In the past, the English language had its fair share of terms to describe the state of being infatuated with a person who does not return your feelings. There was unrequited love for those who prefer more flowery language or crush for those with a more casual flair. Alas, these terms failed on one front: They assigned responsibility for the situation to the person having the feelings. They even went so far as to imply that the object of the affection has no obligation whatsoever to return the feelings (or have sex with someone as a consolation prize). Thus, the angry dudes of the Internet came up with the term friend zone, which shifts the locus of responsibility from the subject to the object of the crush. It implies that, as the object is at fault for "putting" her admirer into the friend zone, it is her duty to do something to remove him from it, preferably by getting naked.
Unsurprisingly, the masses are fond of this new term. (And let's be honest: While men and women of all sexual orientations get crushes, the friend zone is mostly a straight-male phenomenon based on the widespread sexist belief that straight men can never truly be friends with women without having an ulterior motive.) It’s so popular, in fact, that it is now being put in the Oxford English Dictionary, a sacred tome widely believed to be both a better dictionary and a better step stool than, say, Merriam-Webster.
All this demonstrates what Jane Austen was trying to tell us 200 years ago: Sometimes it doesn't pay to let a guy down easy. Many a woman has uttered the phrase "Let's just be friends" on the theory that something a little more direct would result in an angry reaction. But really, even if your suitor goes so far as to cough up a word that starts with a b or even a c, is that really worse than having him go on Tumblr and write self-pitying posts about how the woman who belongs to him refuses to accept her fate? If you suspect that you're dealing with a guy who is comfortable with the term friend zone, then there's no reason not to be blunt in your rejection, preferably by saying, "I could never be with a man whose beard smells like Cheeto dust."
Obviously, there is no need to adopt a blanket policy of shooting down all offers with cruelty. Many men have the social graces to take a hint and don't need you to be insulting in order to move along with no animus in their hearts. With a little practice, a lady can tell the difference between men with these social graces and men who are going to complain online about what a heartless friend-zoner you are. Red flags to look out for: inordinate amounts of time spent on Reddit, My Little Pony paraphernalia in his home or on his Facebook page, a tendency to use terms like alpha and beta male, and a paranoid belief that women in Princess Leia costumes have set out to destroy him. Naturally, such a group of men in no way encompasses all of male geekdom, which is full of men who manage to have both comic-book collections and the ability to understand that they aren't owed a woman's attention. But when dealing with those flying the red flags, women would do well to understand that you can't win with them, so don't even try.