flatline

/ˈflætˌlaɪn/
verb (intransitive) (informal)
1.
to die or be so near death that the display of one's vital signs on medical monitoring equipment shows a flat line rather than peaks and troughs
2.
to remain at a continuous low level
Contemporary definitions for flatline
verb

to die

Word Origin

from the flat line displayed on a heart monitor when the heart stopped functioning

Usage Note

slang; also flatline n.

verb

See flatline

Word Origin and History for flatline
v.

by 1998, from the flat line on an electrocardiogram or electroencephalogram when the patient is dead. Related: Flatlined; flatlining.

Slang definitions & phrases for flatline

flatline

modifier

Dead: The defendant's face was flatline

verb

To die: State government is in a coma. We're going to flat-line at any moment

[1980s+; fr the flat line showing no waves, hence no heartbeat, on a heart-monitoring machine]