soundtrack

n. narrow band on motion-picture film that holds the sound recording; commercial recording of music and songs used in a film

In film formats, the soundtrack is the physical area of the film which records the synchronized sound. For the early history of the sound track, see the article sound film.
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Noun
1. sound recording on a narrow strip of a motion picture film
(hypernym) sound recording, audio recording
(hyponym) dubbing
(part-holonym) sound film

n. sound track, sounds which accompany the movie, songs that are heard in the movie

n. soundtrack