Here are some possibilities:
* Fern: This is the most likely possibility, as "fernier" could be a misspelling of "fern," which is a type of plant.
* A proper noun: It could be a name, a place, or a brand name.
* A word from another language: It's possible the word "fernier" originates from a different language.
Could you provide more context or details about where you encountered this word? That would help me understand what you're looking for.