Definition of the word flatline

The term "flatline" originates from the field of medical monitoring, specifically in anesthesiology and critical care medicine. In the 1960s, medical professionals used electrocardiograms (ECGs) to monitor patients' hearts. A flatline referred to an ECG reading that showed a complete absence of electrical activity, indicating cardiac arrest or death. In the 1970s and 1980s, the term "flatline" gained popularity in television and film, particularly in medical dramas. It was often used to describe a patient's heart rate that had become so slow or irregular that it appeared as a flat line on the ECG monitor, indicating the patient was clinically dead. Over time, the term "flatline" has been adopted in general language to describe a wide range of concepts, including the absence of activity, excitement, or progress, as well as a stagnant or uneventful situation.