World English Dictionary
flatline (ˈflætˌlaɪn)
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

Collins English Dictionary - Complete & Unabridged 10th Edition
2009 © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins
Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009
Cite This Source
Dictionary.com's 21st Century Lexicon
Main Entry:  flatline
Part of Speech:  v
Definition:  to die
Etymology:  from the flat line displayed on a heart monitor when the heart stopped functioning
Usage:  slang; also flatline n.
Main Entry:  flatline
Part of Speech:  v
Definition:  See flatline
Dictionary.com's 21st Century Lexicon
Copyright © 2003-2014 Dictionary.com, LLC
Cite This Source
Word Origin & History

as a verb, by 1998, from the flat line on an electrocardiogram or electroencephalogram when the patient is dead.
Online Etymology Dictionary, © 2010 Douglas Harper
Cite This Source
Slang Dictionary

flatline definition

  1. in.
    to die. (From the flatness of the line on an EEG monitor when the heart stops.) : It appeared that the patient flatlined during the night.
Dictionary of American Slang and Colloquial Expressions by Richard A. Spears.Fourth Edition.
Copyright 2007. Published by McGraw-Hill Education.
Cite This Source
Copyright © 2014 Dictionary.com, LLC. All rights reserved.
  • Please Login or Sign Up to use the Recent Searches feature