pacemaker meaning and definition

PACEMAKER noun

Definition of pacemaker (noun)

1. a leading instance in its field
   • "the new policy will be a pacesetter in community relations"
   • synonyms: pacesetter
2. a specialized bit of heart tissue that controls the heartbeat
   • synonyms: cardiac pacemaker, SA node, sinoatrial node
3. an implanted electronic device that takes over the function of the natural cardiac pacemaker
   • synonyms: artificial pacemaker
4. a horse used to set the pace in racing
   • synonyms: pacer, pacesetter