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Synonyms

unsure

American  
[uhn-shoor, ‐shur] / ʌnˈʃʊər, ‐ʃɜr /

adjective

  1. not certain or confident.

    He arrived at the party unsure of his welcome.

  2. unknown or liable to change; not determined or definite.

    The monthly trend for this stock is still unsure, but the daily trend is upward.

    What happened next is unsure.


unsure British  
/ ʌnˈʃʊə /

adjective

  1. lacking assurance or self-confidence

  2. (usually postpositive) without sure knowledge; uncertain

    unsure of her agreement

  3. precarious; insecure

  4. not certain or reliable

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Etymology

Origin of unsure

First recorded in 1400–50; Middle English unseur(e) “unsafe; precarious; uncertain”; un- 1 ( def. ) + sure ( def. )

Explanation

If you're unsure, you don't feel confident. It's natural to feel unsure of yourself the very first time you read your poems in front of an audience. When you feel unsure, you find yourself full of doubt. If you remember how unsure you felt on your first day of school, you may want to befriend that new kid who looks unsure about where to sit in class. You can be unsure of yourself, or unsure how to comfort your friend whose cat just died. When this word was originally used in the 15th century, it primarily meant "not safe from attack."

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Vocabulary lists containing unsure

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.

As to whether the software sector can re-emerge as a tech and market leader, Wilson is unsure.

From MarketWatch • Jun. 8, 2026

Osborne says he’s still unsure of the potential market size in dollars, but investors appear to be valuing the industry in the multiple billions.

From Barron's • Jun. 4, 2026

Even so, he is unsure how long the system can survive.

From BBC • May 29, 2026

“We did our jobs right if it made someone a little bit unsure as to whether or not this is an earnest, serious award show, or something that is completely frivolous,” Yang says.

From The Wall Street Journal • May 28, 2026

Kathy, unsure of what else to do and not wanting to relive the moment in school again, picked up the frybread and took a bite.

From "Legendary Frybread Drive-In" by Cynthia Leitich Smith

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