Dictionary.com asks, "did you mean 'unsapient?'" Well, no.
A search of many online dictionaries yields nothing, so far. For sapient, Google says: Adjective: Wise, or attempting to appear wise. Noun: A human of the species homo sapiens.
So, why did I make a note of this word? Sometimes I wish my habits were better as regards such things. I didn't include the source, just the word, all by itself. It was printed somewhere, part of something, meant for a very specific purpose by some writer who, whether skillfully or not, intended to impart a meaning.
Based on a search using the Fweet tool, it's not one of the words in Finnegans Wake.
It's interesting, anyway.