syncopation. Device used by composers in order to vary position of the stress on notes so as to avoid regular rhythm. Syncopation is achieved by accenting a weak instead of a strong beat, by putting rests on strong beats, by holding on over strong beats, and by introducing a sudden change of time-signature. First used at time of ars nova, and exploited to fullest capabilities by jazz musicians, often in improvisation. Stravinsky, Bartók, etc. also employ syncopation with dramatic effect.