Obsolete form of none.
"The archaic manuscript uses the spelling "non" instead of the modern "none.""
In plain English: Non means not, used to say something is false or doesn't happen.
"The non-smoking area is right next to the restaurant entrance."
Usage: The adverb "non" is an obsolete form of "none" and should not be used in modern writing. Instead, use "not" or "none" depending on whether you are negating a verb or referring to no people or things.
Derived from Latin, non originally meant "not" and functions as an adverb used to negate verbs or other words. It entered English directly in the late 14th century without significant alteration of its core meaning.