non-: Used in the sense of no or none, to show lack of or failure to perform; or in the sense of not, to negate the meaning of the word to which it is prefixed. Non- is used in front of nouns to form nouns which refer to situations where a particular action has not or will not take place. He was disqualified from the council for non-attendance. Both countries agreed on non-interference in each other's internal affairs. NON- definition: a prefix meaning “not,” freely used as an English formative, usually with a simple negative force as implying mere negation or absence of something (rather than the opposite or reverse of it, as often expressed byun- ): nonadherence; noninterference; nonpayment; nonprofessional. NON- definition: 1. used to add the meaning not or the opposite of to adjectives and nouns: 2. used to add the…. Learn more. Search the world's information, including webpages, images, videos and more. Google has many special features to help you find exactly what you're looking for. used with many words to change their meanings to the opposite; not. Find similar words to non- using the buttons below. Non- definition: Not. Definition of non- prefix in Oxford Advanced Learner's Dictionary. Meaning, pronunciation, picture, example sentences, grammar, usage notes, synonyms and more. The meaning of NON- is not : other than : reverse of : absence of. How to use non- in a sentence. The English prefix non-, which means “not,” appears in hundreds of English vocabulary words, such as non sense, non fat, and non returnable. You can remember that the prefix non- means “not” via the word non poisonous, for a substance that is non poisonous is “not” poisonous.