1. an unspecified or unknown thing; some thing: he knows something you don't; take something warm with you. 2. an unspecified or unknown amount; bit: something less than a hundred. 3. an impressive or important person, thing, or event: isn't that something?. The Beatles performing “Something.” Anthology Collection CD & vinyl box sets out now: The meaning of SOMETHING is some indeterminate or unspecified thing. How to use something in a sentence. Something is a song by the English rock band the Beatles from their 1969 studio album Abbey Road. It was written by George Harrison, the band's lead guitarist. SOMETHING definition: 1. an object, situation, quality, or action that is not exactly known or stated: 2. a thing for…. Learn more. You use something to refer to a thing, situation, event, or idea, without saying exactly what it is. He realized right away that there was something wrong. There was something vaguely familiar about him. The garden was something special. SOMETHING definition: some thing; a certain undetermined or unspecified thing. See examples of something used in a sentence.