Nonce-word is not.
A nonce-word is one created “for the nonce,” for a specific one-time occasion or use. For instance, if I were to declare much of the wordplay in this book as my personal for-the-moment noncence, I’d be creating a nonce-word, a pun on nonsense. It’s said that longtime Oxford English Dictionary editor James Murray created it in 1884 (well, the Oxford English Dictionary is among those that said it, so it’s probably true).
My favorite nonce-word comes from Joseph Kell’s novel Inside Mr Enderby: “The intermittent drone was fmneganswaked by lightly sleeping Enderby into a parachronic lullaby chronicle.” Kell is what we might call a nonce-de-plume, a pen name used once by one Anthony Burgess, author of A Clockwork Orange, the novel filled with a concocted dialect called nadsat. Burgess as Kell using the name of James Joyce’s nonce-terpiece Finnegans Wake to create a nonce-verb . . . ah, the artifice is simply delicious. (The Joseph Kell pseudonym was apparently so well hidden that the Yorkshire Post sent a copy of Inside Mr Enderby to Burgess to review; Burgess shrugged, did not say “What the Kell?” and proceeded to review his own book.)
Meanwhile, back to the topic at hand: the word nonce-word, once itself a nonce-word, is no longer itself, as we now use it all the time.
And that nonessential fact is also a noncential fact. 5