ˈ ̷ ̷ˌ ̷ ̷ ̷ ̷ noun
1.
a. : one that sets the pace for another — called also pacesetter
b. : one that takes the lead or sets an example
ought to act as pacemaker of Europe unity — F.E.Hirsch
2.
a. : a body part (as the sinoatrial node of the heart) that serves to establish and maintain a rhythmic activity
b. : an emergency device for stimulating the heart with an alternating current to steady the beat or to reestablish the rhythm of an arrested heart
time it takes for the electrical impulse to travel from the pacemaker at the base of the heart — P.D.White