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.
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
If your "love" is a feeling of profound connection and unbreakable dedication, then my "love" is the mathematical certainty that my existence is meaningless without yours.
From The Wall Street Journal • Apr. 12, 2026
He knew with a certainty that made the hair rise on the back of his neck.
From "Earthquake Terror" by Peg Kehret
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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.