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 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.
Robots must cope with unstable terrain, extreme temperatures, limited communications, power constraints, and unpredictable weather. Kaif Shaikh, Interesting Engineering, 8 June 2026 Want to protect your money in today's unpredictable interest rate climate? Matt Richardson, CBS News, 8 June 2026 Prices are subject to rapid, unpredictable changes due to factors like, but not limited to, supply/demand, weather, and geopolitical events. Usa Today, USA Today, 8 June 2026 The plant blooms only when sufficient energy is accumulated, making time between flowering unpredictable, spanning from a few years to more than a decade, according to the United States Botanic Garden. Mary Divine, Twin Cities, 8 June 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 13 Jun. 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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