Let's go to the American heritage Dictionary:
Human effort to imitate, supplement, alter, or counteract the work of nature.
The conscious production or arrangement of sounds, colors, forms, movements, or other elements in a manner that affects the sense of beauty, specifically the production of the beautiful in a graphic or plastic medium.
The study of these activities.
The product of these activities; human works of beauty considered as a group.
High quality of conception or execution, as found in works of beauty; aesthetic value.
A field or category of art, such as music, ballet, or literature.
A nonscientific branch of learning; one of the liberal arts.
A system of principles and methods employed in the performance of a set of activities: the art of building.
A trade or craft that applies such a system of principles and methods: the art of the lexicographer.
Skill that is attained by study, practice, or observation: the art of the baker; the blacksmith's art.
Skill arising from the exercise of intuitive faculties: "Self-criticism is an art not many are qualified to practice" (Joyce Carol Oates).
Artful devices, stratagems, and tricks.
Artful contrivance; cunning.
Printing Illustrative material.
You will note that NOWHERE does it define art as "Whatever the "artist" claims is art."
Keys hanging on a fence is no more "art" than keys hanging on the wall at the locksmith's shop.
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