flat-out

1 of 2

adjective

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

flat out

2 of 2

adverb

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 : absolutely, downright
usually used as an intensive
is just flat-out confusing

Examples of flat-out in a Sentence

Adjective regarded their son-in-law as a flat-out loser and let him know it 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.
Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Adjective
It’s been flat-out difficult to score for both sides. Mark Lazerus, New York Times, 29 Apr. 2025 Explore Ray Vaughn See latest videos, charts and news As Vaughn settles in the second time around, his voice is gruff, worn from rapping, recording, interviewing, and flat-out existing. Mackenzie Cummings-Grady, Billboard, 28 Apr. 2025
Adverb
But Hellebuyck flat out missed on Jimmy Snuggerud’s second-period goal, allowing the Blues to tie the game with Scheifele out, the Jets reeling and Winnipeg’s power play failing to score earlier in the frame. Jeremy Rutherford, New York Times, 1 May 2025 Earlier this week, China flat out denied statements from both Trump and members of his administration that suggested the U.S. and Beijing were engaged in talks to forge a deal. Brian Evans, CNBC, 1 May 2025 See All Example Sentences for flat-out

Word History

First Known Use

Adjective

1906, in the meaning defined at sense 1

Adverb

1932, in the meaning defined at sense 1

Time Traveler
The first known use of flat-out was in 1906

Browse Nearby Words

Cite this Entry

“Flat-out.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/flat-out. Accessed 11 May. 2025.

Last Updated: - Updated example sentences
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