The meaning of NOT is —used as a function word to make negative a group of words or a word. How to use not in a sentence. NOT definition: 1. used to form a negative phrase after verbs like "be", "can", "have", "will", "must", etc…. Learn more. Learn what not means with clear definitions, pronunciation, synonyms, and real-world examples. Simple explanations to help you use not correctly. NOT definition: (used to express negation, denial, refusal, or prohibition). See examples of not used in a sentence. Not is often shortened to n't in spoken English, and added to the auxiliary or modal verb. For example, 'did not' is often shortened to 'didn't'. (used before a singular count noun) not even one (expressing emphasis about the lack of something):[~ + a/one + noun] He had not a penny to his name. Not a single missile got through the defense system. 'Not' is a commonly used negative marker and pro-sentence in the English language. In this lesson, we will discuss how to learn and use it. Definition of not adverb in Oxford Advanced Learner's Dictionary. Meaning, pronunciation, picture, example sentences, grammar, usage notes, synonyms and more. The adverb not is used for negation. Do you like drinking cod liver oil? No, I do not like drinking cod liver oil. In this case not cannot appear after the verb; some authorities recommend placing it before to to avoid a split infinitive, but for most speakers the forms not to do and to not do are more or less interchangeable, with the latter being mostly informal.