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flatten

[ flat-n ]
/ ˈflæt n /
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See synonyms for: flatten / flattened on Thesaurus.com

verb (used with object)
to make flat.
to knock down: The boxer flattened his opponent in the second round.
verb (used without object)
to become flat.
Verb Phrases
flatten in, Nautical. flat1 (def. 61).
flatten out, Aeronautics. to fly into a horizontal position, as after a dive.
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Origin of flatten

First recorded in 1620–30; flat1 + -en1

OTHER WORDS FROM flatten

flat·ten·er, nouno·ver·flat·ten, verb (used with object)un·flat·tened, adjective
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2022

How to use flatten in a sentence

British Dictionary definitions for flatten

flatten
/ (ˈflætən) /

verb
(sometimes foll by out) to make or become flat or flatter
(tr) informal
  1. to knock down or injure; prostrate
  2. to crush or subduefailure will flatten his self-esteem
(tr) music to lower the pitch of (a note) by one chromatic semitoneUsual US word: flat
(intr foll by out) to manoeuvre an aircraft into horizontal flight, esp after a dive

Derived forms of flatten

flattener, noun
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
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