Dictionary.com
definitions
  • synonyms

flatten

[flat-n]
See more synonyms on Thesaurus.com
verb (used with object)
  1. to make flat.
  2. to knock down: The boxer flattened his opponent in the second round.
verb (used without object)
  1. to become flat.
Verb Phrases
  1. flatten in, Nautical. flat1(def 61).
  2. flatten out, Aeronautics. to fly into a horizontal position, as after a dive.

Origin of flatten

First recorded in 1620–30; flat1 + -en1
Related formsflat·ten·er, nouno·ver·flat·ten, verb (used with object)un·flat·tened, adjective

Synonyms

See more synonyms on Thesaurus.com
2. ground, fell, prostrate, deck, floor.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for flattener

flatten

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

Word Origin and History for flattener

flatten

v.

late 14c., "to prostrate oneself," also "to fall flat," from flat (adj.) + -en (1). Meaning "to make flat" is 1620s. Related: Flattened; flattening.

Online Etymology Dictionary, © 2010 Douglas Harper