Heartbeat (noun)

1. The sound made by the heart as it pumps blood through the body.
2. The regular contraction and expansion of the heart, which can be felt as a pulse.

Origin:

Heartbeat (n.) from heart (n.) + beat (n.).

Examples:

1. He could hear the heartbeat of the foetus.
2. She was checking her own heartbeat with a stethoscope.
3. The heartbeat was strong and steady.
4. He was measuring the heartbeat with an ECG.
5. She was feeling the heartbeat of the patient.