I had to Google that word. FYI: 

"cromulent. adjective. Appearing legitimate but actually being spurious : These citations are indeed cromulent. [a word used by the schoolteacher, Miss Hoover, in an episode of The Simpsons, in which she defended one made-up word by making up another]"

"(humorous) Fine, acceptable or normal; excellent, realistic, legitimate or authentic."

"Used in an ironical sense to mean legitimate, and therefore, in reality, spurious and not at all legitimate. Assumes common knowledge of the inherent Simpsons reference."