flatten

verb

flat·​ten ˈfla-tᵊn 

flattened; flattening 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

ˈflat-nər 

ˈfla-tə-

noun

Synonyms

• even
• level
• plane
• smooth
• smoothen

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

The positive news is that despite headliners within the past few months about companies mandating return to the office, overall, the number has flattened out over the past couple quarters. —Rachel Wells, Forbes, 6 Dec. 2024

To flatten the cell like a squashed raisin so that the internal structures spread out. —The Physics Arxiv Blog, Discover Magazine, 2 Dec. 2024

Instead, the Maui Invitational’s homecoming after being played in Honolulu last year arrives against the backdrop of an island, and community, still reeling from August 2023’s devastating wildfires: blazes that claimed at least 102 lives, displaced thousands of locals and flattened an entire town. —Brendan Marks, The Athletic, 25 Nov. 2024

Spatchcocking is the process of flattening a bird after removing the backbone. —Christine Rousselle, Fox News, 25 Nov. 2024

Word History

First Known Use

1630, in the meaning defined at transitive sense

Kids Definition

flatten

verb

flat·​ten ˈflat-ᵊn 

flattened; flattening ˈflat-niŋ 

-ᵊn-iŋ

: to make or become flat