In economics, a luxury good (or upmarket good) is a good for which demand increases more than proportionally as income rises, so that expenditures on the good become a greater proportion of overall spending.
Luxury goods are in contrast to necessity goods, where demand increases proportionally less than income.[1] Luxury goods is often used synonymously with superior goods and Veblen goods.
The word "luxury" originated from the Latin word “Luxus,” which means indulgence of the senses, regardless of cost.source:
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