* A misspelling: Check if you meant a similar-sounding name like "Nisha," "Nyasha," or "Natasha."
* A personal name: It could be a unique name created by someone or a name specific to a particular culture or region.
* A fictional name: It might be a character name from a book, movie, or video game.
To figure out the meaning, you need more context.
For example, if you saw "Nysha" in a book, tell me the book's title and author. If you heard it from someone, tell me where you heard it (like, "My friend's name is Nysha").