Editing Tuple (section)

==Etymology==
The term originated as an abstraction of the sequence: single, couple/double, triple, quadruple, quintuple, sextuple, septuple, octuple, ..., {{math|''n''}}‑tuple, ..., where the prefixes are taken from the [[Latin]] names of the numerals. The unique 0-tuple is called the ''null tuple'' or ''empty tuple''. A 1‑tuple is called a ''single'' (or ''singleton''), a 2‑tuple is called an ''ordered pair'' or ''couple'', and a 3‑tuple is called a ''triple'' (or ''triplet''). The number {{math|''n''}} can be any nonnegative [[integer]]. For example, a [[complex number]] can be represented as a 2‑tuple of reals, a [[quaternion]] can be represented as a 4‑tuple, an [[octonion]] can be represented as an 8‑tuple, and a [[sedenion]] can be represented as a 16‑tuple.

Although these uses treat ''‑tuple'' as the suffix, the original suffix was ''‑ple'' as in "triple" (three-fold) or "decuple" (ten‑fold). This originates from  [[medieval Latin]]  ''plus'' (meaning "more") related to [[Greek language|Greek]] ‑πλοῦς, which replaced the classical and late antique ''‑plex'' (meaning "folded"), as in "duplex".<ref>''OED'', ''s.v.'' "triple", "quadruple", "quintuple", "decuple"</ref>{{efn|Compare the etymology of [[ploidy]], from the Greek for -fold.}}