It is possible that:
* It's a misspelling: Check for typos and try alternative spellings.
* It's a regional word: It might be a dialectal or slang term used in a specific location.
* It's a fictional word: It could be from a book, movie, or game.
* It's a personal name: Perhaps it's a name in a specific language or culture.
Could you provide more context about where you encountered the word "lioth"? Knowing the source might help decipher its meaning.