pacemaker
UK: ˈpeɪsmeɪkə | US: ˈpeɪsmeɪkər
n. a device implanted in the heart to regulate its rhythm
n. a person or thing that sets the speed or standard in a race or activity
The word "pacemaker" combines "pace" (from Latin passus, meaning "step" or "speed") and "maker" (Old English macian, "to create"). Originally used in sports (early 20th century) for a runner who sets the pace, it later evolved in medicine (1960s) to describe the heart-regulating device, metaphorically extending the idea of "setting the rhythm."
The surgeon implanted a pacemaker to stabilize the patient's heartbeat.
She acted as the pacemaker for the marathon, keeping a steady speed.
Technological advancements have made pacemakers more efficient.
Without a pacemaker, his heart would beat irregularly.
The team captain served as the pacemaker during training sessions.