meter) or sextuple time (chiefly British) is a musical metre characterized by six beats in a measure.
A time signature of 188 or 1816, however, does not necessarily mean that the bar is a sextuple metre with each beat divided into three.
It may, for example, be used to indicate a bar of triple metre in which each beat is subdivided into six parts.
[1] In this case, the metre is sometimes characterized as "triple sextuple time".
An example of a piece in true sextuple time is Charles-Valentin Alkan's Barcarolette in E♭ minor, No.