Dictionary.com
Thesaurus.com
Synonyms

implausible

American  
[im-plaw-zuh-buhl] / ɪmˈplɔ zə bəl /

adjective

  1. not plausible; not having the appearance of truth or credibility.

    an implausible alibi.
    Synonyms:
    unbelievable, improbable, unlikely
implausible British  
/ ɪmˈplɔːzəbəl /

adjective

  1. not plausible; provoking disbelief; unlikely

"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

Other Word Forms

  • implausibility noun
  • implausibleness noun
  • implausibly adverb

Etymology

Origin of implausible

First recorded in 1595–1605; im- 2 + plausible

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.

The “deal of valuation,” Aswath Damodaran says Citrini’s viral AI doomsday scenario is implausible.

From MarketWatch • Mar. 5, 2026

The judge said Motin's version of events was "extremely implausible".

From BBC • Feb. 5, 2026

But those implausible sci-fi scenarios, believe it or not, are nowhere near the worst-case possibilities.

From Salon • Jan. 18, 2026

Mr. Stephens comments in a way that exalts the passage’s author: “Given this statement, it seems implausible that . . . Marcus bowed to trumpery.”

From The Wall Street Journal • Jan. 11, 2026

One might think that Schaffer or his readers would have rejected these arguments as inherently implausible.

From "The Invention of Science" by David Wootton

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.