isorhythm
A technique that arranges a fixed pattern of pitches with a repeating rhythmic pattern, used in some medieval motets and in more recent works.
countable, uncountable
In his motets Machaut strove for all-over patterns of rhythmic unity through isorhythms, a system codifying a few set patterns of time value, the number of repetitions of a pattern within a composition depending upon the desired length […]
Where it comes from
Borrowed from German Isorhythmik, coined in 1904 by composer Friedrich Ludwig (1895-1970) (iso- + rhythm).
Adapted from the Wiktionary entry isorhythm (CC BY-SA 4.0).