A low, continuous sound, often indistinct or soft, made by a group of people speaking quietly or by a gentle movement of air or water. The murmur of the crowd filled the auditorium as people settled into their seats.
A softly spoken or almost inaudible utterance. She heard a murmur of agreement from the back of the room.
A quiet or subdued expression of discontent or dissatisfaction. There was a murmur of disapproval when the new policy was announced.
An abnormal sound heard during a heartbeat, typically indicating a problem with the heart valves. The doctor detected a heart murmur during the patient's routine check-up.