quadruples

Quadruple is a term used to denote a group or arrangement of four parts. The plural form, quadruples, can refer to multiple such four-part structures or, in everyday usage, simply the plural of the noun quadruple. In mathematics, a quadruple is an ordered 4-tuple, often written as (a, b, c, d). If the elements come from four sets A, B, C, and D, the Cartesian product A × B × C × D comprises all possible quadruples with first, second, third, and fourth components drawn from those sets. For finite sets, the number of quadruples is the product |A| × |B| × |C| × |D|.

In computer science, quadruples appear as an intermediate representation of code known as four-address or quadruple form. An instruction is typically encoded with four fields: operator, argument1, argument2, and result, enabling a compact, four-field depiction of operations in compiler design and program analysis.

In biology, quadruples (more commonly called quadruplets) refer to four offspring born in a single birth event. While quadruplets is the standard term, quadruples may be encountered in wider texts or informal usage.

Beyond these domains, quadruple often means fourfold or four times as much. It is used to describe increases by a factor of four, or to characterize fourfold achievements, such as a team completing a quadruple of major trophies in a season in sports reporting. The term also appears in higher-level contexts to describe four-element data structures, four-component systems, or other four-part arrangements.