Someone who tries at something, fails misserably, and lets into pop culture so they can have more money.
Bowling for Soup is the biggest sell out. They used to be alternative but things didn't go so great so they decided to be on pop stations, so now they do more things for pop stations than for alternative just because of the money. Fuck sellouts
Conor Oberst/Bright Eyes, or any other formerly indie band who signs with Sony Records and starts appearing in teen magazines, much to the chagrin of all their devoted fans. See fucker, asswipe, and bitch.
"Conor Oberst is a fuckingsellout because he appeared in ELLEgirl, YM, and Seventeen magazines, and because his new album 'I'm Wide Awake, It's Morning' sucks enormous ass and is riddled with covers and duets with shitty artists such as Emmylou Harris."