Webster's Revised Unabridged Dictionary · 1913

Non

Non (non) , adjective

No; not. See No, a. — Chaucer

Non- (non-) , prefix

[Latin non, Old Latin noenu, noenum, from neoenum, lit., not one. See None.]

A prefix used in the sense of not; un-; in-; as in nonattention, or non-attention, nonconformity, nonmetallic, nonsuit.

The prefix non- may be joined to the leading word by means of a hyphen, or, in most cases, the hyphen may be dispensed with. The list of words having the prefix non- could easily be lengthened.