Short form of Arthur, possibly from Celtic 'artos' meaning bear, or Irish 'art' meaning stone.
Art achieves something that few names manage: it functions as both a complete name and an abstraction. Standing alone, it was widely used as an independent given name through the nineteenth and early twentieth centuries, particularly in Ireland and America, where it carried the easy authority of a man who needed nothing extra. It also served, and continues to serve, as the most natural short form of Arthur — a name of famously tangled etymology, variously traced to the Celtic "artos" (bear), the Roman clan name Artorius, and even early Welsh linguistic roots.
The legendary King Arthur, whatever his historical basis, embedded the longer form permanently in the mythology of Arthurian Britain: the Round Table, Guinevere, Merlin, Excalibur, and the promise to return in Britain's darkest hour. The standalone Art produced a remarkable roster of American cultural figures in the twentieth century. Art Tatum, the jazz pianist, is widely considered the most technically gifted instrumentalist in the history of the genre — his speed and harmonic invention astonished contemporaries including Fats Waller, who reportedly announced Tatum's arrival in a club by saying "I only play piano, but tonight God is in the house."
Art Garfunkel, the singer and actor, gave the name a gentle, intellectual quality. Art Buchwald, the political satirist, gave it a wry, street-smart edge. Art Deco — the interwar design movement — linked the name permanently to a particular vision of geometric modernity and glamour, even though the movement itself was named retrospectively.
For parents today, Art sits at the intersection of several appealing currents: the revival of short, punchy vintage names (Ike, Hal, Bud); the Irish-American tradition of simple, strong given names; and the quiet appeal of a name that doubles as a noun describing the highest human creative impulse. It is a name that has never been fashionable enough to feel dated and never obscure enough to feel invented.