NO definition: 1. not any; not one; not a: 2. used in signs and on notices to show that something is not allowed…. Learn more. You use no to acknowledge a negative statement or to show that you accept and understand it. (used to express dissent, disagreement, denial, or refusal, as in response to a question or request, or in giving a command): Can we leave now?''— No, stay here.'' No (adverb, noun, adjective) - Used to describe the absence of something when expected or supposed. No is one of the most commonly used words in many languages around the world. no是一个多词性的英语单词，主要用作感叹词、限定词、副词、名词和形容词 [4-5]。 作为感叹词或副词时，no用于否定回答、否定陈述、表示惊讶或禁止，例如“Any problems?” — “No, I‘m O.K.”，也可用于纠正之前的话，如“I was twenty-two — no, twenty-one.”。 The meaning of NO is not. How to use no in a sentence. No is the ultimate negative: it means not any, or not at all, and it's also used to express a generally negative response. If there's no milk for your cereal in the morning, there's not a drop left. 1. not any, not a, or not one: there's no money left; no card in the file. 2. not by a long way; not at all: she's no youngster. 3. (followed by comparative adjectives and adverbs) not: no fewer than forty men; no more quickly than before. No is the ultimate negative: it means not any, or not at all, and it's also used to express a generally negative response. If there's no milk for your cereal in the morning, there's not a drop left.