unpredictable

adjective

un·​pre·​dict·​able ˌən-pri-ˈdik-tə-bəl How to pronounce unpredictable (audio)
Synonyms of unpredictable
: 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
ˌən-pri-ˈdik-tə-blē How to pronounce unpredictable (audio)
adverb
changes that occur unpredictably
unpredictability
ˌən-pri-ˌdik-tə-ˈbi-lə-tē How to pronounce unpredictable (audio)
noun
the unpredictability of the weather

Synonyms of unpredictable

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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.
That would, in turn, enable them to constantly search for drones, low-flying warplanes, and even cruise missiles flying in unpredictable trajectories. — Paul Iddon, Forbes.com, 30 Aug. 2026 Cornstarch could also break down and affect soil microbes in unpredictable ways. — Leanne Potts, Better Homes & Gardens, 30 Aug. 2026 Landslides, debris flows and glacial lake outburst floods are all features of the area that are becoming more unpredictable with climate change. — Simone McCarthy, CNN Money, 29 Aug. 2026 Researchers from Tohoku University in Japan and VISTEC in Thailand say the approach could help robots move more effectively through unpredictable terrain. — Jijo Malayil, Interesting Engineering, 28 Aug. 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

Rhymes for unpredictable

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Browse Nearby Words

unpredictability
unpredictable
unpredicted
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Cite this Entry

“Unpredictable.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/unpredictable. Accessed 1 Sep. 2026.

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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
Last Updated: - Updated example sentences
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