\ ˈflat-ˌau̇t How to pronounce flat-out (audio) \

Definition of flat-out

 (Entry 1 of 2)

1 : being or going at maximum effort or speed
2 : out-and-out, downright it was a flat-out lie

flat out


Definition of flat out (Entry 2 of 2)

1 : in a blunt and direct manner : openly called flat out for revolutionNat'l Review
2 : at top speed or peak performance the car does 180 m.p.h. flat out
3 usually flat-out \ ˈflat-​ˌau̇t How to pronounce flat-out (audio) \ : absolutely, downright usually used as an intensiveis just flat-out confusing

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Examples of flat-out in a Sentence

Adverb I told him flat out that I have no intention of marrying him. We asked for more time but they refused us flat out. The car does 180 mph flat out.
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Recent Examples on the Web: Adverb The European bourses were flat out of the gates, but perked up throughout the morning. Bernhard Warner, Fortune, "The U.S. shopper puts investors in a good mood, sending global shares higher," 17 June 2020 Other changes improve cooling so the Mach 1 can run flat out all day: 50% increase in engine oil cooling, 75% more cooling for the 10-speed. Mark Phelan, Detroit Free Press, "Ford Mustang Mach 1 to return to streets after 17-year absence. Here's what it looks like," 16 June 2020 So the notion that Wall Street can't thrive with a Democratic president is flat out wrong. Paul R. La Monica, CNN, "The stock market no longer cares whether Trump wins," 10 June 2020 Some are just flat out funny, with nothing more on their minds than the spritz of escapism. Peter Rainer, The Christian Science Monitor, "Home theater: Films that invoke the pleasures of summer," 9 June 2020 Floyd’s death has lit a new fire in the nation calling out for justice and equality for all Black lives and prompted some newer calls to flat out defund police departments across the nation. Breanna Edwards, Essence, "Minneapolis City Council Signals Commitment To Dismantle Its Police Department," 8 June 2020 There’s a difference between delayed consumption and spending that just flat out won’t happen because people stayed home and didn’t go on spring break. Diego Mendoza-moyers, ExpressNews.com, "What’s in the $2 trillion stimulus package for San Antonio," 27 Mar. 2020 In our half-mask tests, the iPhone flat out refused to unlock for us. Michelle Maltais, USA TODAY, "Your iPhone won't recognize you in a face mask – but a Samsung Galaxy might," 10 Apr. 2020 But there’s a flip side: data and information can be manipulated to mislead or flat out deceive. Paul Todd, STAT, "Expertise can help save us from Covid-19 — if we use it right," 6 May 2020

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'flat-out.' 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 flat-out


1906, in the meaning defined at sense 1


1932, in the meaning defined at sense 1

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Time Traveler for flat-out

Time Traveler

The first known use of flat-out was in 1906

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Statistics for flat-out

Cite this Entry

“Flat-out.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/flat-out. Accessed 6 Jul. 2020.

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More Definitions for flat-out


How to pronounce flat out (audio)

English Language Learners Definition of flat-out

 (Entry 1 of 2)

chiefly US : absolute and complete
: greatest possible

flat out


English Language Learners Definition of flat out (Entry 2 of 2)

chiefly US : in a very clear and direct way
: at the fastest possible speed
US, informal used to make a statement more forceful


\ ˈflat-ˌau̇t \

Kids Definition of flat-out

1 : out-right entry 2 sense 1 That's a flat-out lie.— Phyllis Reynolds Naylor, Shiloh
2 : greatest possible a flat-out effort

flat out


Kids Definition of flat out

1 : in a very clear manner I told him flat out to leave.
2 : at top speed We worked flat out to finish.

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More from Merriam-Webster on flat-out

Thesaurus: All synonyms and antonyms for flat-out

Rhyming Dictionary: Words that rhyme with flat-out

Spanish Central: Translation of flat-out

Comments on flat-out

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