certainty
Americannoun
plural
certainties-
the state of being certain.
- Synonyms:
- confidence, assurance, certitude
-
something certain; an assured fact.
- Synonyms:
- truth
idioms
noun
-
the condition of being certain
-
something established as certain or inevitable
-
without doubt
Related Words
See belief.
Other Word Forms
- noncertainty noun
Etymology
Origin of certainty
1250–1300; Middle English certeinte < Anglo-French, equivalent to certein certain + -te -ty 2
Explanation
A certainty is a sure thing, something we know is true or will happen without any doubt. Here's a certainty: One plus one is two. And here's another: The earth orbits the sun. The noun certainty comes from the Latin word certus, meaning "sure" or "fixed." Besides being something that is certain, the word can also refer to a state of mind, like the confidence you feel when you know something is completely true or right. For example, you might speak with certainty about your decision to move to the big city and pursue your dream of becoming a famous actor. (But that doesn't necessarily mean becoming a famous actor is a certainty.)
Vocabulary lists containing certainty
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.
It wasn’t long ago that counting on a mega cap tech stock to rise was a pretty safe bet, but that certainty has been turned on its head this year.
From Barron's • Apr. 4, 2026
The only certainty is that this problem is a thorny one, and there is plenty of ground to cover over the next few weeks.
From BBC • Apr. 3, 2026
We take it day by day, week by week, like adults who have finally accepted that certainty is an illusion.
From Los Angeles Times • Apr. 3, 2026
So the team asked the state to grant them a payment-in-lieu-of-taxes, something commonly used in real-estate development to mitigate risk by creating tax certainty.
From The Wall Street Journal • Apr. 1, 2026
You cannot use just the genotype—BRCA1 mutation—to predict the final outcome with certainty.
From "The Gene" by Siddhartha Mukherjee
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.
