What does the prefix nonus mean?

The prefix "nonus" is not a recognized prefix in the English language. There might be a misunderstanding or a typo.

Could you please provide more context or clarify what you are looking for?

For example, are you perhaps thinking of:

* "non-": This prefix means "not" or "the opposite of".

* "nona-": This prefix, derived from the Latin word for "ninth", indicates a position or order within a series.

If you could provide more information, I might be able to help you understand the prefix you are looking for.