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.
That hasn’t stopped Americans from pushing back against the certainty of taxes—death is another matter—since the cry of “no taxation without representation” helped spark the Revolutionary War.
From Barron's • Apr. 14, 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
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
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.
