unsure

adjective

un·​sure ˌən-ˈshu̇r 

-ˈshər,

 especially Southern  -ˈshȯr

: not marked by or given to feelings of confident certainty : not sure

was unsure of what to do

Phrases

unsure of oneself

: lacking confidence in one's abilities

… he's a little unsure of himself when it comes to the music world …

—Seth Mnookin

Synonyms

• skeptical
• suspicious
• uncertain
• doubtful

Examples of unsure in a Sentence

unsure of her ability to handle the pressure of competing in the Olympic Games

Recent Examples on the Web

Tom Brady likely wasn't unsure of his position, just as Michael Jordan probably never questioned his role on the team. —John Gallucci Jr, Forbes.com, 4 Aug. 2025

Now, those who want to be vaccinated in the fall are unsure if the vaccine will be available to them and if their insurance will cover the cost. —Jade Walker, CNN Money, 4 Aug. 2025

Researchers are unsure why boys appear to be most at risk of being infected. —Janet Loehrke, USA Today, 3 Aug. 2025

Scientists are unsure how long the fish have lived in Devils Hole, which is thought to have formed 60,000 years ago. —Austin Corona, AZCentral.com, 2 Aug. 2025

Word History

First Known Use

15th century, in the meaning defined above

Rhymes for unsure

• abjure
• adjure
• allure
• assure
• brochure
• cocksure
• coiffure
• contour
• couture
• demure
• detour
• endure