Medical Dictionary
pacemaker
noun pace·mak·er \ˈpā-ˌsmā-kər\
Medical Definition of PACEMAKER
1
: a group of cells or a body part (as the sinoatrial node of the heart) that serves to establish and maintain a rhythmic activity
2
: an electrical device for stimulating or steadying the heartbeat or reestablishing the rhythm of an arrested heart—called also pacer
Seen & Heard
What made you want to look up pacemaker? Please tell us where you read or heard it (including the quote, if possible).