flatten

verb flat·ten \ ˈfla-tᵊn \

Updated on: 16 May 2018

Definition of flatten

flattened; flattening play \ˈflat-niŋ, 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

play \ˈflat-nər, ˈfla-tə-\ noun

See flatten defined for English-language learners

See flatten defined for kids

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 of flatten from the Web

The pre-dawn barrage flattened Iranian military compounds, intelligence facilities and munition warehouses in Syrian territory, Israel said, describing the assault as the nation's largest air operation in years.

— greg norman, Fox News, "Israel's takedown of Iranian targets in Syria proves military, compared to Tehran's, packs a powerful punch," 10 May 2018
Its latest product to be approved, a treatment for the rare spinal muscular atrophy, got out to a promising start on the market but has since flattened.

— damian garde, STAT, "As Biogen turns 40, biotech worries the glory days may be over," 2 May 2018
He was knocked around by silly perceptions, pushed backward by injury concerns, then ultimately flattened with an absolute sucker punch from his former coach Jim Mora.

— bill plaschke, latimes.com, "Rosen says nine teams made mistakes by passing on him," 27 Apr. 2018
Watch him flatten the rusher from LSU in one highlight.

— zak keefer, Indianapolis Star, "From picked on to punishing: The story of new Colt Quenton Nelson," 27 Apr. 2018
While investors debate the meaning of the flattening curve, one factor that could propel yields higher is increased government borrowing.

— daniel kruger, WSJ, "Yields on 10-Year Treasurys Cross 3% Threshold," 24 Apr. 2018
Even if Facebook’s user base flattens or begins to go down (the number of U.S. and Canadian daily Facebook users declined for the first time ever last quarter), Instagram's popularity is still exploding.

— taylor antrim, Vogue, "Is Drake’s "Nice for What" A Problem for Instagram?," 13 Apr. 2018
In action, this meant that rather than my hair being blown around—which flattens curls and adds frizz—the Supersonic diffuser dries your hair faster, while still keeping your curls defined.

— abigail mccoy, Glamour, "The New Dyson Supersonic Hair Dryer Ended My 20-Year Battle Against Frizz," 26 Apr. 2018
Separately, the state will increase the cigarette tax to $1.10 a pack — an increase of 50 cents — and flatten the individual income tax rate to 5 percent for all incomes, replacing a scale of rates between 2 percent and 6 percent.

— grace schneider, The Courier-Journal, "What the recent tax reform bills mean for the average Kentuckian," 19 Apr. 2018

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.