OK, what's Indie?

[Mr Peabody]

It took years for it to dawn on me that "prog" was short for progressive rock, so this time I will just ask, what is Indie? Am I classificationally challenged?

[Stone]

It took years for it to dawn on me that "prog" was short for progressive rock, so this time I will just ask, what is Indie? Am I classificationally challenged?

"Indie" is short for independent, which really was originally descriptive of artists on "independent" labels, that is labels that were/are not major labels. The term "indie" has really taken on a life of its own and is used differently by different people. There's an explanation from AMG here.