flat·​line | \ ˈflat-ˌlīn How to pronounce flatline (audio) \
flatlined; flatlining; flatlines

Definition of flatline

intransitive verb

1a : to register on an electronic monitor as having no brain waves or heartbeat
b : die
2a : to be in a state of no progress or advancement
b : to come to an end

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Other Words from flatline

flatliner noun

Synonyms & Antonyms for flatline



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Examples of flatline in a Sentence

the patient was fading fast, and doctors expected him to flatline before the night was over
Recent Examples on the Web Economists surveyed by Wolters Kluwer Blue Chip Economic Indicators predict growth of 2.3% at an annual rate in the current quarter, according to their average estimate, but some expect GDP to flatline or even dip. Paul Davidson, USA TODAY, "Economy grew 4% in the fourth quarter as COVID-19 raged, consumers curtailed spending, contracted 3.5% in 2020," 28 Jan. 2021 Global emissions may flatline around current record levels, putting the world on track for a temperature increase of about 3 degree Celsius, International Energy Agency Executive Director Fatih Birol told delegates. Mathew Carr, Bloomberg.com, "Climate and Coronavirus Dominate Oil Industry’s Biggest Summit," 10 May 2020 In recent years, the oil industry has crept slowly toward an existential challenge everyone knew was coming with a growing crop of analysts predicting that demand for oil would flatline sometime in the coming decades before declining. Justin Worland, Time, "Oil Prices Won't Be Negative Forever. But the Oil Industry Will Never Be the Same," 20 Apr. 2020 That combination could flatline U.S. electric car sales in 2020, BNEF says, adding that estimate could even be revised down further. Josh Siegel, Washington Examiner, "Daily on Energy: Coronavirus could flatline US electric car sales," 13 Mar. 2020 So the possibility that his Open career might flatline with last year’s mundane T-52 at Pebble Beach seems a cruel jest. Eamon Lynch, Golfweek, "19th hole: Are we facing Phil’s final act?," 9 Feb. 2020 And all this musical angst, rendered in what often feel like the same endless vamps, soon starts to flatline. Ben Brantley, New York Times, "Review: Peter Dinklage Tackles ‘Cyrano’ Without the Nose," 7 Nov. 2019 The weak price pressure is causing GDP to flatline. Bernhard Warner, Fortune, "Europe Has a Germany Problem, and It’s Spreading to Global Markets," 23 Sep. 2019 Advanced economies could flatline their emissions tomorrow and all would still be lost. David Roberts, Vox, "The climate change policy with the most potential is the most neglected," 11 July 2019

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'flatline.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of flatline

1980, in the meaning defined at sense 1a

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Time Traveler for flatline

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The first known use of flatline was in 1980

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Statistics for flatline

Last Updated

11 Feb 2021

Cite this Entry

“Flatline.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/flatline. Accessed 4 Mar. 2021.

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More Definitions for flatline

flat·​line | \ ˈflat-ˌlīn How to pronounce flatline (audio) \
flatlined; flatlining

Medical Definition of flatline

1 : to register on an electronic monitor as having no heartbeat or brain waves : to experience cessation of heart contractions or brain wave activity as indicated by a flat line on a electrocardiogram or electroencephalogram I flatlined on the operating table, but Dr. Bunsom managed to revive me.— Alison Wright, Yoga Journal, May/June 2005 He used to be ill quite a bit as a younger child, and his heart flatlined four times before he was 6.— Ginnie Graham, Tulsa World, 19 Dec. 2007
2 : die entry 1 But just because death is expected doesn't mean it's any less depressing when the patient finally flatlines.— Phil Taylor, Sports Illustrated, 26 Jan. 2009

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