certainty
Americannoun
-
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
Synonym Usage
See belief.
Other Word Forms
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.
As for trade uncertainty, Greer said everyone should know if they want absolute certainty, they should source as much as possible from the U.S.
From Barron's • May 27, 2026
The only certainty is the Division 1 final will be played on Friday at 7 p.m. at Cal State Fullerton unless either of the finalists has a scheduling issue on that date.
From Los Angeles Times • May 26, 2026
The authors rated the cleaned analysis as high certainty, but the effect was small, suggesting that supplementation is not a dramatic brain boost for everyone.
From Science Daily • May 22, 2026
"I need that multi-year budget, particularly for the farming community in Northern Ireland, giving certainty in terms of the support that we wish to deliver, not just in this year, but in future financial years."
From BBC • May 21, 2026
The missing puzzle piece I’d mentioned to Elliot slammed into place with a certainty and clarity that literally took my breath away.
From "Glitch" by Laura Martin
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.
