I don't think meaningful cultural content works. A national flag has that, but isn't art.

If one wants a definition, I would say this: the difference between art and non-art is profundity. Non-art, including, since the matter has been raised, wooden indians and ships' figureheads, is all on the surface. What you see at once is all there is. A work of art you can come back to and see something new. A great work of art, you keep seeing new things the more often you look.