Systolic:This refers to the blood pressure when the heart is actively contracting, specifically indicating the peak arterial pressure during the contraction of the heart's left ventricle. The phase when this contraction happens is referred to as systole. In a blood pressure measurement, the systolic pressure is typically the first number noted. For instance, in a blood pressure reading of 120/80 ("120 over 80"), the systolic pressure is 120, representing 120 millimeters of mercury (mm Hg). A systolic murmur is a sound heard during systole, the heart's contraction period, occurring between the usual first and second heart sounds. The word "systolic" is derived from the Greek term "systole," which means "a drawing together or a contraction." This term has been used since the 16th century to describe the heart's contraction phase.