Not so much pedantry as precision from C Ingram:
A nonce-word is a word that is created for the nonce, a word which did not previously exist but whose meaning is made transparent by the context. They can be very effective in the right hands, and they usually need a particular aesthetic to make them work. They must feel right, as well as working semantically. Such words are rarely picked up by anyone to be used again, and so remain as unique examples in the written (or spoken) language.
Then there is the hapax legomenon, which classically educated readers will recognise as meaning spoken once. This refers to a particular text or body of language, so it is possible to say that ‘…’ is a hapax in the King James Bible, or that ‘Honorificabilitudinitatibus’ is a hapax in Shakespeare. There are also hapaxes in the whole of a corpus of language used for linguistic research, which these days are very large, or in English literature generally.