unpredictable
Americanadjective
noun
adjective
Other Word Forms
Derived Forms
Etymology
Origin of unpredictable
First recorded in 1855–60; un- 1 + predictable
Explanation
When something's unpredictable, it doesn't happen at expected times or it can't be predicted. If trains were unpredictable, they wouldn't follow a set schedule and you'd never know when one would arrive. The adjective unpredictable can also describe something that's unexpected or not known in advance. Your soccer team's skill level might be wildly unpredictable — from game to game your coach never knows what you guys will do. It can be an insult if someone calls you an unpredictable person. That means people can't rely on you for things, such as consistently good work or keeping your promises.
Vocabulary lists containing unpredictable
Power Prefix: un-
Looking to grow your vocabulary? Check out this interactive, curated word list from our team of English language specialists at Vocabulary.com – one of over 17,000 lists we've built to help learners worldwide!
Speak
Interested in learning more words like this one? Our team at Vocabulary.com has got you covered! You can review flashcards, quiz yourself, practice spelling, and more – and it's all completely free to use!
Twenty Thousand Leagues Under the Sea
Want to remember this word for good? Start your learning journey today with our library of interactive, themed word lists built by the experts at Vocabulary.com – we'll help you make the most of your study time!
Example Sentences
Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.
Just as the sport itself is unpredictable, there is no telling which way this new experiment in three-way hosting will go.
From BBC • Jun. 4, 2026
After all the buildup, fear and uncertainty, the most wide-open and unpredictable California gubernatorial primary in decades appears to have ended in the most consistent and predictable of ways.
From Los Angeles Times • Jun. 3, 2026
The job for some can be unpredictable and lonely.
From The Wall Street Journal • May 28, 2026
The company has been trying to increase its higher-margin prepared foods business to reduce its dependence on unpredictable commodity cycles.
From Barron's • May 28, 2026
Liam was a great many things, but mysterious and unpredictable weren’t included in that deck of cards.
From "The Darkest Minds" by Alexandra Bracken
Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.
