Systole /(?)/

Sys·to·le

Systole

n.
  1. The shortening of the long syllable. (Gram.)
  2. The contraction of the heart and arteries by which the blood is forced onward and the circulation kept up; also, the contraction of a rhythmically pulsating contractile vacuole; -- correlative to diastole. (Physiol. & Biol.)