flatten

American  

[flat-n] / ˈflæt n /

verb (used with object)

1. to make flat.

2. to knock down.

   The boxer flattened his opponent in the second round.

   Synonyms:

   floor, deck, prostrate, fell, ground

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verb (used without object)

1. to become flat.

verb phrase

1. flatten out to fly into a horizontal position, as after a dive.

2. flatten in flat.

flatten British  

/ ˈflætən /

verb

1. (sometimes foll by out) to make or become flat or flatter

2. informal (tr)

   1. to knock down or injure; prostrate

   2. to crush or subdue

      failure will flatten his self-esteem

3. Usual US word: flat.  (tr) music to lower the pitch of (a note) by one chromatic semitone

4. to manoeuvre an aircraft into horizontal flight, esp after a dive

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Other Word Forms

• flattener
  noun
• overflatten
  verb (used with object)
• unflattened
  adjective

Etymology

Origin of flatten

First recorded in 1620–30; flat ¹ + -en ¹

Explanation

When you flatten something, you crush it or level it out. If the recycling bin is getting full, you should probably flatten all those cans you're adding to it. You might flatten the batter in a cake pan before baking it, or flatten the grass along a path through a field. If your curly hair tends to get frizzy in humid weather, you may try to flatten it before you leave for school in the morning. You also might flatten yourself against a wall if you're hiding from your friend, or describe a terrible storm this way: "The tornado managed to flatten several buildings."

Example Sentences

Flatten and squash boxes to make more room in your recycling bin, bag or box.

From BBC • Dec. 22, 2022

Flatten with a spatula to approximately ¾-inch thick.

From Fox News • Aug. 14, 2021

“Flatten the curve, go home! Flatten the curve, go home!” a man in New York’s Brooklyn borough yelled out the window of a four-story apartment building, as people walked on the street below.

From Reuters • Mar. 16, 2020

By your C.E.O.’s work station: Flatten hierarchies by sobbing in front of your company leader.

From New York Times • Nov. 9, 2018

Flatten it by striking with broad blade of knife or a cleaver.

From The Century Cook Book by Ronald, Mary

Related Words

• crush
• raze
• smash
• straighten