flatten

verb

flat·​ten ˈfla-tᵊn How to pronounce flatten (audio)
flattened; flattening ˈflat-niŋ How to pronounce flatten (audio)
ˈfla-tə-

transitive verb

: to make flat: such as
a
: to make level or smooth
b
: to knock down
also : to defeat decisively
c
: to make dull or uninspired
often used with out
d
: to make lusterless
flatten paint
e
: to stabilize especially at a lower level

intransitive verb

: to become flat or flatter: such as
a
: to become dull or spiritless
b
: to extend in or into a flat position or form
c
: to become uniform or stabilized often at a new lower level
usually used with out
flattener
ˈflat-nər How to pronounce flatten (audio)
ˈfla-tə-
noun

Examples of flatten in a Sentence

Dozens of houses were flattened by the tornado. The boxer was flattened in the seventh round. The team got flattened in the first round of the play-offs. Prices are expected to flatten after the holiday shopping season.
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.
One image in the show that follows that thread is a famous photograph of Dresden, Germany, taken from the top of the city hall after Dresden was flattened by Allied aerial bombing at the end of World War II. Nina Siegal, New York Times, 7 May 2025 Developers had already flattened most of the dunes north to the Virginia border. Amy Brecount White, Smithsonian Magazine, 6 May 2025 For every race that’s run across the country, each horse is assigned a Beyer speed rating, based on an algorithm designed to flatten out variances between different race lengths and track conditions. Greg Rosenstein, NBC news, 4 May 2025 With their computer algorithms touting compatibility, swiping has flattened our romantic interest. Alex Abad-Santos, Vox, 3 May 2025 See All Example Sentences for flatten

Word History

First Known Use

1630, in the meaning defined at transitive sense

Time Traveler
The first known use of flatten was in 1630

Cite this Entry

“Flatten.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/flatten. Accessed 18 May. 2025.

Kids Definition

flatten

verb
flat·​ten ˈflat-ᵊn How to pronounce flatten (audio)
flattened; flattening ˈflat-niŋ How to pronounce flatten (audio)
-ᵊn-iŋ
: to make or become flat

More from Merriam-Webster on flatten

Last Updated: - Updated example sentences
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