systole

English Thesaurus

1. the contraction of the chambers of the heart (especially the ventricles) to drive blood into the aorta and pulmonary artery (noun.event)

hypernym	:	beat, heartbeat, pulsation, pulse,
definition	:	the rhythmic contraction and expansion of the arteries with each beat of the heart (noun.event)

hyponym	:	extrasystole,
definition	:	a premature systole resulting in a momentary cardiac arrhythmia (noun.event)