- a person, horse, vehicle, etc, used in a race or speed trial to set the pace
- a person, an organization, etc, regarded as being the leader in a particular field of activity
- Also called: cardiac pacemaker a small area of specialized tissue within the wall of the right atrium of the heart whose spontaneous electrical activity initiates and controls the beat of the heart
- Also called: artificial pacemaker an electronic device for use in certain cases of heart disease to assume the functions of the natural cardiac pacemaker
WordReference Random House Learner's Dictionary of American English © 2026
pace•mak•er /ˈpeɪsˌmeɪkɚ/USA pronunciation
n. [countable]
WordReference Random House Unabridged Dictionary of American English © 2026- pacesetter.
- Medicinean electronic device surgically placed beneath the skin to provide a normal heartbeat by electrically stimulating the heart muscle.
pace•mak•er
(pās′mā′kər),USA pronunciation n.
pace′mak′ing, n.
- pacesetter.
- Medicinean electronic device implanted beneath the skin for providing a normal heartbeat by electrical stimulation of the heart muscle, used in certain heart conditions.
- Physiology, Anatomy[Anat., Physiol.]any specialized tissue that governs a rhythmic or cyclic biological activity, as the sinoatrial node of the heart that controls heartbeat.
- pace1 + maker 1880–85
Collins Concise English Dictionary © HarperCollins Publishers::
pacemaker /ˈpeɪsˌmeɪkə/ n
'pacemaker' also found in these entries (note: many are not synonyms or translations):