unsure
Americanadjective
-
not certain or confident.
He arrived at the party unsure of his welcome.
-
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.
adjective
-
lacking assurance or self-confidence
-
(usually postpositive) without sure knowledge; uncertain
unsure of her agreement
-
precarious; insecure
-
not certain or reliable
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."
Vocabulary lists containing unsure
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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.
Union representatives say mixed messaging has left employees unsure whether they can rely on upcoming paychecks.
From Barron's • Apr. 10, 2026
The company lost focus, unsure if it was selling to sneakerheads or soccer moms.
From The Wall Street Journal • Mar. 31, 2026
In the absence of clear communication, and amid an ongoing internet blackout, many described feeling exposed and uncertain, unsure when or where the next strike might hit.
From BBC • Mar. 27, 2026
Scientists were unsure whether those dips were caused by dark spots on the star or by material orbiting nearby.
From Science Daily • Mar. 27, 2026
Pong cut his motor and stared, unsure what to do.
From "A Wish in the Dark" by Christina Soontornvat
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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.