non

Non is most often used in English as a prefix meaning "not" or "without." It is added to nouns and adjectives to form words that describe something outside a group, missing a quality, or not doing a certain action. A non-smoker is a person who does not smoke. Non-fiction is writing that is not fictional. A non-essential item is not necessary.

This prefix is very common in everyday English, formal writing, and technical language. You may see it in words like nonverbal, nonresident, nonhuman, nonviolent, and nonrenewable. In each case, the prefix changes the base word by denying it or marking it as outside the usual category. It often signals absence, exclusion, or exception rather than a complete opposite.

Spelling can vary. Some forms are written with a hyphen, especially when that makes the word easier to read, as in non-stop or non-native. Other forms are often written as one word, such as nonfiction or nonresident. In short, non is a small but very useful prefix that helps English clearly express "not," "without," or "outside a certain kind."