I've always gone with this definition:
Something that has been deliberately constructed to evoke specific thoughts and or emotions.
Fine art or high art:
A: does the above so badly so that only 'experts' can work out (or at least think they can) what was attempting to be evoked.
B: Has been made by someone with the right art world connections.
C: Has been made by someone famous or infamous (considered shit until you are told it's by that guy who went nuts and cut his ear off and sent it to someone).