flatten

[flat-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

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

/ 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

Other Word Forms

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

Word History and Origins

Origin of flatten¹

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

Example Sentences

As the helium hisses out, the volunteers flatten the plastic skin, tucking in Snoopy’s ears or SpongeBob’s nose to prepare for the final roll.

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The Treasury yield curve flattened a bit to start the week as the 10-year Treasury yield fell by about 3 basis points, while the 2-year yield ticked lower by less than 1.

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A much-touted nuclear renaissance in the early 2000s fizzled when electricity demand flattened and the shale boom delivered abundant, cheap natural gas.

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“We inherited this terrible inflation. We are flattening it out. I believe we are going to push it down,” he told Bartiromo.

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Its crimson eyes almost glow with hunger and its pupils flatten in anger.

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Related Words

• crush 
• raze 
• smash 
• straighten