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 is against the backdrop of the Iran war, with no certainty about where the ceasefire might stand during the state visit.
From BBC • Apr. 10, 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
This includes long-term contracts to replenish munitions stocks so defense contractors can invest in production lines with more certainty.
From The Wall Street Journal • Apr. 2, 2026
Ben Reitzes: The certainty is that the rate of change will be accelerating.
From Barron's • Mar. 27, 2026
Thus I have moral certainty that Caesar crossed the Rubicon, and moral certainty that Pascal accurately reported the Puy-de-Dôme experiment.
From "The Invention of Science" by David Wootton
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.
