uncertain

adjective un·cer·tain \ ˌən-ˈsər-tᵊn \
Updated on: 19 Nov 2017

Definition of uncertain

1 a :not known beyond doubt :dubious
  • an uncertain claim
b :not having certain knowledge :doubtful
  • remains uncertain about her plans
c :not clearly identified or defined
  • a fire of uncertain origin
2 :not constant :variable, fitful
  • an uncertain breeze
3 :indefinite, indeterminate
  • the time of departure is uncertain
4 :not certain to occur :problematical
  • his success was uncertain
5 :not reliable :untrustworthy
  • an uncertain ally

uncertainly

adverb

uncertainness

play \ˌən-ˈsər-tᵊn-(n)əs\ noun

Examples of uncertain in a Sentence

  1. The time of departure is still uncertain.

  2. We are still uncertain of the truth.

  3. She remains uncertain about her plans.

  4. I'm uncertain about how to respond.

  5. The cause of the fire is uncertain.

  6. He has an uncertain temper.

  7. They face a financially uncertain future.

Recent Examples of uncertain from the Web

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

First Known Use of uncertain

14th century



UNCERTAIN Defined for English Language Learners

uncertain

adjective

Definition of uncertain for English Language Learners

  • : not exactly known or decided : not definite or fixed

  • : not sure : having some doubt about something

  • : not definitely known


UNCERTAIN Defined for Kids

uncertain

adjective un·cer·tain \ ˌən-ˈsər-tᵊn \

Definition of uncertain for Students

1 :not exactly known or decided on
  • an uncertain amount
2 :not sure
  • They were uncertain of the rules.
3 :not known for sure
  • an uncertain claim
4 :likely to change :not dependable
  • uncertain weather

uncertainly

adverb


Seen and Heard

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

Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!

WORD OF THE DAY

marked by intense feeling

Get Word of the Day daily email!

Test Your Vocabulary

Find the Cousins

  • a-large-tree-with-many-branches
  • Which pair shares a common word ancestor?
True or False

Test your knowledge - and maybe learn something along the way.

TAKE THE QUIZ
SCRABBLE® Sprint

Test Your Knowledge - and learn some interesting things along the way.

TAKE THE QUIZ

Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!