Decrease

Decrease is a noun describing a reduction in size, amount, extent, or value, and a verb meaning to become smaller or to cause something to become smaller. It can describe a lower quantity, level, or degree, and is often used with numbers, measurements, or rates. The term derives from the Latin decrescere, meaning to grow less, and entered English via Old French.

In mathematics, a sequence is called decreasing if each term is less than or equal to the previous one. A function is decreasing on an interval when its value decreases as the input increases. In calculus, a negative derivative indicates a decrease in the function’s value. In statistics and data analysis, a downward trend or a decrease indicates a reduction over time.

In economics and everyday use, a decrease can refer to lower prices, reduced demand, smaller production, or cooler temperatures. A decrease in inflation, for example, means prices rise more slowly or fall. Absolute and percentage forms are common: the absolute decrease equals initial minus final, and the percent decrease equals (initial minus final) divided by initial, times 100%.

Related terms include decline, reduction, and diminution. Decrease emphasizes downward change, while increase denotes the opposite. The concept appears across disciplines, from numerical measurements to natural phenomena and economic indicators.

Examples: The population decreased by 12% over the decade. Costs decreased by 15% after the new efficiency measures.