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soundtrack

American  
[sound-trak] / ˈsaʊndˌtræk /

noun

  1. the narrow band on one or both sides of a motion-picture film on which sound is recorded.

  2. the sound recorded on a motion-picture film; audio portion of a film.

  3. the music or dialogue from a film available on a commercial recording.

soundtrack British  
/ ˈsaʊndˌtræk /

noun

  1. the recorded sound accompaniment to a film Compare commentary

  2. a narrow strip along the side of a spool of film, which carries the sound accompaniment

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

verb

  1. (tr) to provide a continuous accompaniment of sounds, esp music

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Etymology

Origin of soundtrack

First recorded in 1925–30; sound 1 + track

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.