Mr.Playstation on 12 March 2015
OK after further research and I quote ( The urban dictionary ):
"Short for Independent Games. These are games partially or (mostly) fully developed by unofficial game developers."
We now need to further break this down:
An unofficial game developer is a group of people or one person who well frankly don't have a company and are developing a game or mod by themselves, with no funding.
Therefore Journey and the like do not form part of the indie spectrum, mods are practically the only games which form part of the indie spectrum.
That's the whole theory I can make up 
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