quadrupled

Quadrupled is the past tense and past participle of the verb quadruple. It means that a quantity has been increased fourfold, or multiplied by four. In mathematics, if a value quadruples, it changes from x to 4x. In everyday usage, a quantity that has quadrupled has grown to four times its original amount. For example, if a city's population rises from 200,000 to 800,000, the population has quadrupled.

As a verb form, quadrupled describes a completed change. It can appear in passive constructions such as “revenue has quadrupled,” or in active sentences like “the company quadrupled its output.” The term emphasizes a fourfold increase and is common in scientific, economic, and statistical writing.

As an adjective, quadrupled can describe a noun that has four times the earlier value, though fourfold is often used for clarity and conciseness. Quadrupled is more specific to the idea of a completed fourfold increase and can appear in formal reports and analyses.

Related terms include fourfold, quadruple, and quadruplicate, all denoting multiplication by four. Fourfold typically denotes a ratio or factor, while quadruple and quadruplicate function as verbs or adjectives in broader usage; quadrupled specifically marks a completed fourfold increase.

Etymology: Quadrupled derives from the verb quadruple, which originates in Latin quadruplex meaning fourfold, from quattuor (four) and plex (fold). The English form has developed through Old French and other intermediaries into modern usage.