The meaning of NO is not. How to use no in a sentence. 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. “NO” by Meghan TrainorListen to Meghan Trainor: more Meghan Trainor videos: . Definition of NO. in the Definitions.net dictionary. Meaning of NO. What does NO. mean? Information and translations of NO. in the most comprehensive dictionary definitions resource on the web. This disambiguation page lists articles associated with the title No. If an internal link incorrectly led you here, you may wish to change the link to point directly to the intended article. Girl, all you gotta say is (Ooh) [Chorus] My name is no, my sign is no, my number is no, uh You need to let it go, uh You need to let it go, uh Need to let it go, uh Nah to the ah to the no, no. 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.