Um, epic nom nom time? Totes! Awks, but did you peep her hooking up? FML. Today suuu-uucks. Total fail! Just wanna get wasteyface tonight. This will probably be incoherent in the near future, because most slang dies young. But why?
Slate explores the complex linguistic evolutionary tree behind words like groovy (embarrassing to use!), cool (timeless and perfect!) and many others that have fallen out of use. According to UNC linguist Connie Eble, a few factors help certain term catch on and stay entrenched.
First, and maybe most importantly, is brevity. We'll use cool as the paragon of slang, because it's extremely old, and still ubiquitous. We say it daily. There is, perhaps, an argument that cool isn't really slang anymore, by virtue of its own linguistic success. But Eble says it's thrived in part because it's short and easy.
Easiness is another factor. Cool is easy to say. It sounds normal. People will not be saying "epic nom nom" in 100 years. Cool is a "real word," without the connotations of, you know, coolness. Bling is cringe-inducing, because it's so arbitrary in construction. Blech.
This process, of constant birth and quick death, has only been accelerated by technology. Killer app? Dead and buried. At least I hope so. "Cyber" is a prefix I'm always loathe to use, because it feels like something from an early-90s PSA video. L33t—is that even a thing anymore? Sexting—probably too confused to live.