Final answer:
A heart murmur is an abnormal sound heard during the heartbeat, caused by the turbulent flow of blood in the heart. It can be normal in certain populations but is considered abnormal in adults.
Step-by-step explanation:
The sound described in the question is known as a heart murmur. A heart murmur is an abnormal sound heard during the heartbeat, caused by the turbulent flow of blood in the heart. It can be normal in people younger than 30 years old and in women in late stages of pregnancy. However, in adults, it is considered an abnormal sound and may indicate an underlying heart condition that warrants further evaluation and testing.