flatline

A flatline is a term used in medicine and electronics to describe a situation where a reading on a monitor or graph shows no change over a period of time. In a medical context, it most commonly refers to an electrocardiogram (ECG) displaying a straight, horizontal line, indicating the absence of electrical activity in the heart. This is a sign of cardiac arrest, where the heart has stopped beating. Medical professionals interpret a flatline as a critical emergency requiring immediate resuscitation efforts.

Beyond cardiology, the term "flatline" can be applied to any monitoring system that shows a constant, unchanging value. For example, in electronics, a battery's voltage might flatline as it discharges, or a signal's amplitude might flatline if the source stops transmitting. In computing, a server's performance might be described as flatlining if it is not processing any requests.

The visual representation of a flatline is universally understood as a lack of activity or a cessation of function. It signifies a state of stasis or complete inactivity in the system being monitored. The implications of a flatline vary greatly depending on the context, ranging from a life-threatening medical emergency to a simple observation of a system at rest or depleted.