noun

flatline

FLAT-lyn

Flatline (noun) means a continuous, unbroken line on a monitor showing that a heart or brain has stopped functioning. Example: “The monitor showed a flatline moments after his heart stopped.”

noun

A continuous, unbroken line on a monitor showing that a heart or brain has stopped functioning.

"The monitor showed a flatline moments after his heart stopped."

verb

To stop functioning entirely, especially the heart; by extension, to stop changing or growing.

"The patient flatlined twice before being stabilized."

"Company profits flatlined after the initial launch surge."

How to use flatline

Learner’s notes

In plain EnglishLiterally, a heart or brain monitor going dead flat; figuratively, something that has stopped growing or changing at all.

Common pairings

flatline on the monitor growth has flatlined

Word forms

flatlined past tense, flatlines plural, flatlines singular

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The monitor showed a _____ moments after his heart stopped.

Etymology

From "flat" + "line" — describing the straight, unmoving trace an ECG or EEG produces when there's no more activity to record.

Rhymes for flatline

nine mine wine line sine dine fine vine pine tine thine shine

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Frequently asked questions

What does “flatline” mean?

The word “flatline” means a continuous, unbroken line on a monitor showing that a heart or brain has stopped functioning. In plain terms, literally, a heart or brain monitor going dead flat; figuratively, something that has stopped growing or changing at all.

How do you pronounce “flatline”?

“Flatline” is pronounced FLAT-lyn (/ˈflætˌlaɪn/ in IPA).

How do you use “flatline” in a sentence?

Here is “flatline” used in a sentence: “The monitor showed a flatline moments after his heart stopped.”

What part of speech is “flatline”?

Depending on how it is used, “flatline” can be a noun and a verb.

How many meanings does “flatline” have?

“Flatline” has 2 distinct senses listed in this dictionary. The most common is: a continuous, unbroken line on a monitor showing that a heart or brain has stopped functioning.