flatline

verb

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

intransitive verb

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

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 But even at a rate of 1 million new arrivals a year, U.S. population growth would flatline in about 40 years and then slowly begin to decline, the census says. David Lauter, Los Angeles Times, 19 Jan. 2024 Whelan flatlined, and Reyes had to break the news to Jet and the rest of the team. Christy Piña, The Hollywood Reporter, 18 Jan. 2024 Enrollment levels in the last three years have generally flatlined. Jessika Harkay, Hartford Courant, 8 Jan. 2024 Over the last year, borrowing costs rose and rents flatlined. Alena Botros, Fortune, 30 Dec. 2023 On one hand, wholesale producer prices rose 0.3% in July after flatlining the prior month, a slightly higher reading than analysts expected. WSJ, 14 Aug. 2023 From 2013 to late 2021, the Millennials’ part of the market increased steadily from 28% to 35%, while the Boomers’ portion flatlined at around 30%, and the Gen X’ers declined from 30% to 25%. Shawn Tully, Fortune, 21 Oct. 2023 The bank recently projected that economic growth would flatline through 2024 and into 2025. Eshe Nelson, New York Times, 22 Nov. 2023 Connie Fuller and her husband; Connie Fuller’s electrocardiogram (EKG) showing flatlining. Theresa Tamkins, NBC News, 7 Oct. 2023 See More

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'flatline.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

First Known Use

1980, in the meaning defined at sense 1a

Time Traveler
The first known use of flatline was in 1980

Dictionary Entries Near flatline

Cite this Entry

“Flatline.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/flatline. Accessed 23 Feb. 2024.

Medical Definition

flatline

intransitive verb
flat·​line ˈflat-ˌlīn How to pronounce flatline (audio)
flatlined; flatlining
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
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
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
Last Updated: - Updated example sentences
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