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Synonyms

improbable

American  
[im-prob-uh-buhl] / ɪmˈprɒb ə bəl /

adjective

  1. not probable; unlikely to be true or to happen.

    Rain is improbable tonight.

    Synonyms:
    implausible, doubtful, questionable

improbable British  
/ ɪmˈprɒbəbəl /

adjective

  1. not likely or probable; doubtful; 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

  • improbability noun
  • improbableness noun
  • improbably adverb
  • superimprobable adjective
  • superimprobableness noun
  • superimprobably adverb

Etymology

Origin of improbable

From the Latin word improbābilis, dating back to 1590–1600. See im- 2, probable

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.

If the Hurricanes are going to pull off the improbable and go from the 10th seed to national champions, they’ll have to go through two of the best passers in the country.

From The Wall Street Journal

Making the Bruins’ rally all the more improbable was that much of it came with leading scorer Tyler Bilodeau on the bench with four fouls.

From Los Angeles Times

The more improbable the behavior, the higher its cost.

From Science Daily

If journalism is the first draft of history, TV news is a rough, improbable sketch.

From Los Angeles Times

But when second-year quarterback Drake Maye broke out into an improbable MVP contender, he lifted the Patriots to their first AFC East title since Tom Brady was slinging the ball in New England.

From The Wall Street Journal