unpredictable

adjective

un·​pre·​dict·​able ˌən-pri-ˈdik-tə-bəl How to pronounce unpredictable (audio)
: not predictable: such as
a
: not able to be known or declared in advance
unpredictable weather
b
: tending to behave in ways that cannot be predicted
an unpredictable boss
unpredictably adverb
changes that occur unpredictably
unpredictability noun
the unpredictability of the weather

Examples of unpredictable in a Sentence

unpredictable spring weather that makes it really hard to know what to wear
Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Not only are relapses unpredictable but scientists have yet to explain the slow and insidious degeneration that often occurs even without new lesions. Lucinda Rosenfeld, New Yorker, 25 Oct. 2025 These large waves can be erratic and unpredictable. Ca Weather Bot, Sacbee.com, 25 Oct. 2025 His characters were often brutally unpredictable. Joy Williams, Harpers Magazine, 24 Oct. 2025 New York can be very unpredictable and has been this season. James Brizuela, MSNBC Newsweek, 24 Oct. 2025 See All Example Sentences for unpredictable

Word History

First Known Use

1840, in the meaning defined above

Time Traveler
The first known use of unpredictable was in 1840

Browse Nearby Words

Cite this Entry

“Unpredictable.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/unpredictable. Accessed 27 Oct. 2025.

Kids Definition

unpredictable

adjective
un·​pre·​dict·​able
ˌən-pri-ˈdik-tə-bəl
: not predictable
unpredictability
-ˌdik-tə-ˈbil-ət-ē
noun
unpredictably
-ˈdik-tə-blē
adverb

More from Merriam-Webster on unpredictable

Last Updated: - Updated example sentences
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