[ pri-pos-ter-uhs, -truhs ]
See synonyms for preposterous on
  1. completely contrary to nature, reason, or common sense; utterly foolish; absurd; senseless: a preposterous tale.

Origin of preposterous

First recorded in 1535–45; from Latin praeposterus “inverted, reversed, perverted, perverse,” literally, “with the rear part first”; see also pre-, posterior, -ous

synonym study For preposterous

See absurd.

Other words for preposterous

Other words from preposterous

  • pre·pos·ter·ous·ly, adverb
  • pre·pos·ter·ous·ness, noun
  • un·pre·pos·ter·ous, adjective
  • un·pre·pos·ter·ous·ly, adverb
  • un·pre·pos·ter·ous·ness, noun Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

How to use preposterous in a sentence

  • Acceptance rates at top schools have fallen to preposterously low levels.

    The Great College Road Trip | Nick Summers | April 8, 2011 | THE DAILY BEAST
  • The cardboard is preposterously thick—thicker than the wedding invitation of a Saudi sheik.

    What Makes Apple So Erotic | Adam Hanft | January 17, 2009 | THE DAILY BEAST
  • The head itself was preposterously small and was supported on an equally preposterous, thick, short neck.

    Before Adam | Jack London
  • This resolution was made in deference to the opinion of others, and to the public feeling, which was so preposterously excited.

  • Wetherbee stared into the shaven, haunted face thus preposterously thrust at him across the years.

  • But it was a preposterously difficult task to get across an undercut to where he could grasp a stunted tree.

    The Invaders | William Fitzgerald Jenkins
  • Strangely, her glances seemed to have become preposterously mixed.

    The Wolf Cub | Patrick Casey

British Dictionary definitions for preposterous


/ (prɪˈpɒstərəs) /

  1. contrary to nature, reason, or sense; absurd; ridiculous

Origin of preposterous

C16: from Latin praeposterus reversed, from prae in front, before + posterus following

Derived forms of preposterous

  • preposterously, adverb
  • preposterousness, 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