Cromulent?

I'm halfway through Tom Bissell's critical analysis of the aesthetics, rhetoric, and narrative structure of modern epic video games, Extra Lives: Why Video Games Matter, and it's pretty weird to read about all these games I've never played (I stopped playing video games after I conquered Road Rash on the Sega Genesis . . . although I do enjoy an occasional game of MarioKart 8 on the WiiU with my kids) and it was even weirder to stumble upon the word "cromulent" in the book, a word which sounds both made-up and vaguely familiar . . . and that is exactly how it is supposed to sound.