1
: in a blunt and direct manner : openly
called flat out for revolution—
Nat'l Review
Nat'l Review2
: 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
ArsTechnica, 2 June 2025
Besides being flat-out funny, with a wonderful supporting cast including Katherine Hahn and Catherine O’Hara and a host of celebrity cameos, the show is at its best in its meta-moments of delicious self-awareness about the business.
—Howard Homonoff, Forbes.com, 28 May 2025
Luke Smith, New York Times, 6 Apr. 2025
Amtrak is just flat out lying in claiming otherwise and under Joe Biden Amtrak always got its way, commuter services and passengers be damned.
—New York Daily News Editorial Board, New York Daily News, 14 Apr. 2025
See All Example Sentences for flat-out
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Adjective
Races used to be processional here, but the re-profiled turn 10 and the flat-out nature of the last turn have changed all that.
—ArsTechnica, 2 June 2025
Besides being flat-out funny, with a wonderful supporting cast including Katherine Hahn and Catherine O’Hara and a host of celebrity cameos, the show is at its best in its meta-moments of delicious self-awareness about the business.
—Howard Homonoff, Forbes.com, 28 May 2025
Adverb
Norris appeared to pick up his pace and the top three appeared to be driving flat out.
—Luke Smith, New York Times, 6 Apr. 2025
Amtrak is just flat out lying in claiming otherwise and under Joe Biden Amtrak always got its way, commuter services and passengers be damned.
—New York Daily News Editorial Board, New York Daily News, 14 Apr. 2025
See All Example Sentences for flat-out
Cite this Entry
“Flat-out.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/flat-out. Accessed 7 Jun. 2025.
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