The quality of being excessively or pretentiously artistic; an affected or self-conscious concern with art.
From arty plus -ness (suffix forming abstract nouns). Emerged in the late 19th century alongside the adjective arty as a way to describe affected artistic behavior.
The emergence of the word 'arty' and 'artiness' in the Victorian era reflects a real cultural moment when art became something middle-class people could perform and display, making it ripe for satire.
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