Please 2 persons had an argument about when to term a song "a sound track of a movie"

One said it can only be called "A SOUND TRACK of a movie" when/if that particular song is played in the movie.
That is when you watch a particular movie and yout hear that particular-song played at some point during the movie.


The other person said "as long as the song was licenced as a soundtrack amongst several other songs as a "compilation-sound track album". One can also call that particular song "A SOUNDTRACK FOR THE MOVIE".
Meaning that song doesn't necessarily have to be played at some point during the movie.


So first person says "its only called a soundtrack of that movie if that song is eventually played in the movie".


Second person says "it doesn't have to be played at some point during the movie to be called a soundtrack of that movie"


Please those those that are enlightened here and also fair in English, Music , Movies and Entertainment should educate us.


Thank you.

Please Moderators, airmark we need your attention and assistance over here.

What brought up this argument is the current hot song "brown skin girl" by Beyonce featuring wizkid amongst others.


The first one said you can't call it a sound track of that movie if its eventually not played at any point during the movie

The second person said "as long as the Sound Track album compilation spearheaded by Beyonce, has that particular track(brown skin girl) in that album, you can as well call that track(brown skin girl) a soundtrack, even if its not eventually played at any point during the movie.

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Amazingman:
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People learn everyday. At times thru differential opinions.