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

Definition of flatten

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

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Other Words from flatten

flattener \ ˈflat-​nər How to pronounce flattener (audio) , ˈfla-​tə-​ \ noun

Synonyms & Antonyms for flatten


even, level, plane, smooth, smoothen


rough, roughen

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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.
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Recent Examples on the Web

During the past year, support for the party has flattened. Katrin Bennhold, BostonGlobe.com, "A political murder and far-right terrorism: Germany’s new hateful reality," 7 July 2019 During the past year, support for the party has flattened, and the liberal Greens have recently surged to the top of the polls. Katrin Bennhold, New York Times, "A Political Murder and Far-Right Terrorism: Germany’s New Hateful Reality," 7 July 2019 Armed with nearly a dozen sandbags, two turbine leaf blowers and one bike pump, eight sweaty volunteers unfurled the baby’s flattened skin and inflated it in parts: first, its tiny orange hands. Dan Zak, Washington Post, "Evening in America: What it felt like on Trump’s 4th of July," 5 July 2019 But amid cuts at the state and federal level, investment in scientific research has flattened over the past decade. STAT, "Federally funded research drives nearly one-third of U.S. patents, report finds," 20 June 2019 This approach flattened and obscured the important ways that the Clintons and other New Democrats’ promotion of the market and the role of government was distinct from Ronald Reagan, Milton Friedman, and their followers. Lily Geismer, Vox, "Democrats and neoliberalism," 11 June 2019 During this decade, the landscape of advanced metrics has flattened; all 30 teams employ analytics departments. Andy Mccullough, latimes.com, "How baby boomer managers reach these dang millennial players," 8 June 2019 Crabs that burrow or swim, such as blue crabs, might have flattened, oar-like pairs of hind legs. National Geographic, "How did crabs evolve 'crabbiness'? It's complicated.," 24 Apr. 2019 In the 2012 addition of Soccer Aid the former Spurs, Man Utd and West Ham forward flattened the TV chef with a blindside hit from behind. SI.com, "Soccer Aid 2019: The Best Moments From the Charity Match's History," 16 June 2019

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

1630, in the meaning defined at transitive sense

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Statistics for flatten

Last Updated

11 Jul 2019

Look-up Popularity

Time Traveler for flatten

The first known use of flatten was in 1630

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More Definitions for flatten



English Language Learners Definition of flatten

: to make (something) flat or flatter
: to become flat or flatter
: to knock down (something or someone)


flat·​ten | \ ˈfla-tən How to pronounce flatten (audio) \
flattened; flattening

Kids Definition of flatten

: to make or become flat She flattened herself against the wall.

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More from Merriam-Webster on flatten

Rhyming Dictionary: Words that rhyme with flatten

Thesaurus: All synonyms and antonyms for flatten

Spanish Central: Translation of flatten

Nglish: Translation of flatten for Spanish Speakers

Britannica English: Translation of flatten for Arabic Speakers

Comments on flatten

What made you want to look up flatten? Please tell us where you read or heard it (including the quote, if possible).


to form ideas or theories about something

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