quintuple

Quintuple is an adjective and a verb meaning fivefold or consisting of five parts. It derives from Latin quintus "fifth" and the suffix -uple, related to other multiplicative forms such as quadruple and sextuple.

As an adjective, quintuple describes something five times as large or numerous, for example a quintuple increase or a quintuple dose. The word is often used interchangeably with fivefold, though fivefold is more common in everyday style. As a verb, quintuple means to multiply by five; the past tense is quintupled (e.g., the population quintupled in ten years).

As a noun, quintuple is rare; the usual term is quintuplet for one of five siblings born in the same birth. The plural is quintuplets. In contexts such as statistics or finance, quintuple is used to refer to fivefold amounts or multipliers, while fivefold or quintuple is preferred in formal writing.

Related terms include quadruple (fourfold), sextuple (sixfold), and quintuplet (one of five siblings). The prefix quint- appears in various terms indicating five, reflecting a common system of naming multiples in English.