When a band or solo artist becomes extremely popular and changes the style and sound of their music make more money, and to earn a spot on the "Top 40" music charts.
Perfect examples of sell out artists:

Coldplay

Elton John

Cher
by EJ5 September 3, 2015
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A person who was once your friends, gets a little fame and forgets about you to appease and the followers.
R. Dweck was once friends with us, but now ignores us because he’s a sell out.
by Chet A. W. June 9, 2019
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Sell Outs are people who used to have fun back in the day. Now they invest all their time playing video games such as animal crossing, catching fish like the rare blue gill.
Tyler, “Since when did Chris become such a sell out?? I broke up with him, I miss the old him and being porked so well by him.”
Mario, “You just need to move on already. It doesn’t seem like he’s interested in anything nowadays! I asked him to go on a vacation to California and he doesn’t want to go!!”
Tyler, “Wow, only sell outs deny vacations!”
by Minoy4667 April 11, 2020
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A sell-out is someone who doesn't have a straight life to live because they're always selling out one day to the next.to live one way than another
we all down but that dude is a sell out.
by Sizzyboi October 1, 2020
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