Neologism

A neologism is a newly invented word, whose use isn't yet widespread enough to warrant inclusion in a dictionary.

I enjoy making up words - sometimes to see if they will catch on, sometimes just for the hell of it. Technically, that makes some of them protologisms.

Anachrospasm

A new word, coined earlier today...

anachrospasm /ənakroʊ'spaz(ə)m/ n. An intensely jarring or unsettling episode of déjà-vu.

Sorry about mixing a Greek prefix with a Latin suffix. There aren't many words that do that.