meaning of institution

What does "institution" mean in the following contexts? Does it mean "developing roots in the society to become a fundamental part of it"? Can you please give some synonyms that make them more understandable?

Context #1:

The artwork can be said, then, to insert itself or come into being somewhere in between or ‘around and about’ such activity, either in an immediate, in situ way or as a form of implicit evocation – that may, as I say, be framed by the boundaries of the art institution– of that which is going on or, indeed, taking place.

Context #2:

In Right to theCity, which, as the title suggests, polemically asserts the urban dweller’s claim to participatory citizenship, he writes that such a ‘renewed fete’ was ‘fundamentally linked to play’ and involved, in an echo perhaps of Hall’s ‘modernism in the streets’, ‘subordinating to play rather than to subordinate play to the “seriousness” of culturalism [. . .] Only relatively recently and through institutions has theatre become “cultural”, while play has lost its place and value in society’