isorhythm

Borrowed from German Isorhythmik, coined in 1904 by composer Friedrich Ludwig (1895-1970) (iso- +‎ rhythm).

isorhythm (countable and uncountable, plural isorhythms)

1. (music) A technique that arranges a fixed pattern of pitches with a repeating rhythmic pattern, used in some medieval motets and in more recent works.
   • 1953, Herbert Weinstock, Music as an art, page 31:

     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 […]

   • 1955, Oscar Lee Rigsby, The Sacred Music of Elzéar Genet: Historical and analytical study:

     Even when such preconceived structural arrangements are not used, as in the Gloria of the Machaut Mass, the idea of isorhythm is present in the suggestion of recurring and balancing strophic plans.

   • 2006, Kyle Gann, The Music of Conlon Nancarrow‎:

     Meaning simply "same rhythm," isorhythm refers to the practice of using the same rhythmic pattern, called in fourteenth-century treatises a talea ("cutting"), over and over in one or more part as the structural base for a motet or mass movement.

• isorhythmic
• isorhythmically