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.
The legal framework for the hub, ensuring diplomatic immunity, is to give companies the certainty that they are accountable under U.S. law in the case of civil disputes, Helberg said.
From The Wall Street Journal • Apr. 16, 2026
There is less certainty around the effect on wildfire season in California.
From Los Angeles Times • Apr. 16, 2026
When asked what he would say to local parents watching this footage, he said: "I can say to them with certainty, with confidence, that you should get your treatment done at THQ Taunsa."
From BBC • Apr. 13, 2026
The lack of certainty over when the conflict will end has fueled some negative sentiment among investors, who had hoped for a deal between the two and a plan for reopening the waterway.
From MarketWatch • Apr. 13, 2026
I wanted to ask for further explanation, but something stopped me—the certainty that to do so would be to shout to the room that I didn’t belong there.
From "Educated" by Tara Westover
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.
