Systolic means the maximum blood pressure through the arteries while the left ventricle of the heart is contracting, explains MedicineNet. The systolic pressure is usually the first number in a blood pressure reading. In a blood pressure reading of 110/80, 110 represents the systolic pressure, meaning 110 millimeters of mercury.
The word systolic comes from the Greek word systole, which means a contraction or a drawing together. Systole is the time when the ventricle contracts, notes MedicineNet. Since the 1500s, physicians have used the word systolic to describe a contracting heart muscle.
As of June 2015, a systolic blood pressure reading below 120 is considered normal, between 120 and 139 is borderline high blood pressure or prehypertension, and 140 or higher is high blood pressure or hypertension, according to WebMD.