bradycardia UK /bɹæ.dɪˈkɑː(ɹ).di.ə/US /bɹeɪ.dɪˈkɑɹ.di.ə/ noun1 •The condition of having a slow heartbeat, defined as under 60 beats per minute for an adult.When your resting heart rate is under 60 bpm, providers call it bradycardia. — 2024 formsbradycardias