A word used to describe anything of awesomeness; whatever you want it to mean. It is in the "public denial but private use" stage of a popular word or phrase; meaning that it has become too popular, leading hypocrites everywhere to dramatically overreact to its use with shouts of "ohhhh, it's SOOOO overused" and likewise, although they still use the word themselves.
Person 1: "Dude, I was (gaming, playing a sport, fucking someone, taking a shit, climbing a telephone pole, eating a baby, etc.) and it was so epic!"
Hypocritical asshole: "Epic is so overused..."
Meanwhile, back at the ranch...
Hypocritical asshole: "Dude, that was epic!"
Person 1 (overhears): "Fuckin' hypocritical asshole."