You could understand that the prefix non- signifies “not” by way of the term nonpoisonous, for your substance that may be nonpoisonous is “not” poisonous. As an interjection to negate what was stated before or expose it as sarcasm, it truly is attested by 1900, popularized 1989 by "Wayne's Planet" https://caidenjtyek.vigilwiki.com/6093469/5_simple_statements_about_woven_explained