What is "inferior good"

n. (context economics English) a good that decreases in demand when consumer income rises; having a negative income elasticity of demand.

In economics, an inferior good is a good that decreases in demand when consumer income rises (or rises in demand when consumer income decreases), unlike normal goods, for which the opposite is observed. Normal goods are those for which consumers' demand increases when their income increases. This would be the opposite of a superior good, one that is often associated with wealth and the wealthy, whereas an inferior good is often associated with lower socio-economic groups.

Inferiority, in this sense, is an observable fact relating to affordability rather than a statement about the quality of the good. As a rule, these goods are affordable and adequately fulfill their purpose, but as more costly substitutes that offer more pleasure (or at least variety) become available, the use of the inferior goods diminishes.

Depending on consumer or market indifference curves, the amount of a good bought can either increase, decrease, or stay the same when income increases.