un·​pre·​dict·​able | \ ˌən-pri-ˈdik-tə-bəl How to pronounce unpredictable (audio) \

Definition 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

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Other Words from unpredictable

unpredictably \ ˌən-​pri-​ˈdik-​tə-​blē How to pronounce unpredictably (audio) \ adverb
changes that occur unpredictably
unpredictability \ ˌən-​pri-​ˌdik-​tə-​ˈbi-​lə-​tē How to pronounce unpredictability (audio) \ noun
the unpredictability of the weather

Examples of unpredictable in a Sentence

Recent Examples on the Web

Drivers didn't like it when Talladega Superspeedway was an elimination race because the Alabama track can be so unpredictable. Fox News, "NASCAR's radical 'roval' race in Charlotte could be the event of the year," 27 Sep. 2018 The process for investigating misconduct is so unpredictable, some critics say, that victims of harassment or abuse don’t know whether they will be discouraged, taken seriously or penalized for coming forward. New York Times, "U.N. Cases Read Like ‘Manual in How Not to Investigate’ Sexual Assault," 29 June 2018 Golf is so beautifully unpredictable Four of the top five players and 18 of the top 30 in the world rankings are in the field this week. Daniel Rapaport, SI.com, "Three Quick Thoughts from Friday at the Zurich Classic of New Orleans," 27 Apr. 2018 Still, public valuations are unpredictable and there is no guarantee Slack’s will live up to those expectations. Maureen Farrell, WSJ, "Slack Plans to Follow Spotify on Unconventional IPO Route," 11 Jan. 2019 My initial goal was to get a sense of how unpredictable and costly ER billing is across the country. Sarah Kliff, Vox, "I read 1,182 emergency room bills this year. Here’s what I learned.," 18 Dec. 2018 But the effects of a meth on a person’s demeanor are completely unpredictable and create a particular challenge for officers. Alexis Stevens, The Seattle Times, "Georgia tallies meth’s toll: Nearly 20 percent of those killed by police in state test positive for it," 20 Nov. 2018 The red tides are unpredictable and not all produce a bioluminescence. CBS News, "Bioluminescence from red tide: Algae bloom literally lighting up San Diego waves at night," 9 May 2018 Conner, Cooper and Ryle have had some positive moments of late and the district tournament figures to be as unpredictable and competitive as ever. Shelby Dermer, Cincinnati.com, "Takeaways: Tournaments and conference champions in Greater Cincinnati, May 7," 8 May 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'unpredictable.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of unpredictable

1840, in the meaning defined above

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Last Updated

15 Mar 2019

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Time Traveler for unpredictable

The first known use of unpredictable was in 1840

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More Definitions for unpredictable



English Language Learners Definition of unpredictable

: not capable of being known before happening or being done
: not always behaving in a way that is expected


un·​pre·​dict·​able | \ ˌən-pri-ˈdik-tə-bəl\

Kids Definition of unpredictable

: impossible to predict The king was a completely unpredictable tyrant.— Brian Jacques, Redwall

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Comments on unpredictable

What made you want to look up unpredictable? Please tell us where you read or heard it (including the quote, if possible).


to corrupt or become corrupted

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