unpredictable

adjective

un·​pre·​dict·​able ˌən-pri-ˈdik-tə-bəl How to pronounce unpredictable (audio)
Synonyms of unpredictablenext
: 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.
These dark subhaloes exert unpredictable gravitational forces, giving energy to the stars and pushing their orbits outward. Paul Sutter, Space.com, 20 Apr. 2026 Those changes should also mean F1 drivers spend a little less of their time worrying about energy management, although their hybrid powertrains remain governed by algorithms that have shown the potential to be unpredictable. Jonathan M. Gitlin, ArsTechnica, 20 Apr. 2026 Factories are still unpredictable. Kurt Knutsson, FOXNews.com, 20 Apr. 2026 This dangerous, unpredictable country is full of opportunity. Ben Smith, semafor.com, 20 Apr. 2026 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 23 Apr. 2026.

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

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