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Synonyms

preposterous

American  
[pri-pos-ter-uhs, -truhs] / prɪˈpɒs tər əs, -trəs /

adjective

  1. completely contrary to nature, reason, or common sense; utterly foolish; absurd; senseless.

    a preposterous tale.

    Synonyms:
    ridiculous, excessive, unreasonable

preposterous British  
/ prɪˈpɒstərəs /

adjective

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

"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

Related Words

See absurd.

Other Word Forms

  • preposterously adverb
  • preposterousness noun
  • unpreposterous adjective
  • unpreposterously adverb
  • unpreposterousness noun

Etymology

Origin of preposterous

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

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

Watch as the fluid camerawork makes her kills look nastier, and the preposterous script allows her to outwit her foes, even with the cards stacked against her at every turn.

From Salon • Mar. 29, 2026

Microdramas hew to an established formula, with each installment ending on a cliffhanger that pushes its often preposterous story line toward a final, usually shocking reveal.

From The Wall Street Journal • Mar. 18, 2026

David Hamilton said he could no longer trust the government to handle some files "unsupervised" after being given "preposterous and unacceptable" excuses for not complying with his orders.

From BBC • Mar. 12, 2026

Written by Matthew Parkhill, with Guy Ritchie — who directed Robert Downey Jr. in two steroidal Holmes films — helming some episodes, it’s pulpy and nutty and preposterous, mostly in a good way.

From Los Angeles Times • Mar. 3, 2026

But Pena had an idea—innovative or preposterous, depending on the point of view—of how one might find some Botocudo DNA anyway.

From "1491" by Charles C. Mann