Definition of "flatline" [flatline]

• Asystole; the absence of heart contractions (noun)
• The disappearance of the rhythmic peaks displayed on a heart monitor (noun)
• (of the heart) to stop beating (verb)
• (by extension) to die (verb)
• To stay at the same level, without development; or, to fall. (verb)

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• "The beeping the pilot heard was "flatline" - the long continously beep meaning "you are about to die unless you deploy your canopy NOW" it's the same sound as in heart monitors), which apparently caused him to stop the fast dive, since canopy deployment was logged at 1500 feet :-)"
• "Feel free to insert your own "flatline" or "Flatland" joke here although we strongly frown on juvenile and misogynistic humor, so don't even go there, please."
• "Did they "flatline" with the same % vote as last year or did they go down?"