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
Derived Forms
Inflected Forms
Nouns
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.
See Examples For:
Jocelin’s certainty is absolute; so is the damage it inflicts.
From The Wall Street Journal ● Jul. 22, 2026
Investors are seeking certainty from the experts, and rather than disabuse them of those mistaken hopes, the pros often reinforce them.
From MarketWatch ● Jul. 21, 2026
Farming minister Llyr Gruffydd said the money was a "baseline" that would be ring-fenced for farming, delivering "certainty and stability" for the sector.
From BBC ● Jul. 20, 2026
But for all of Nolan’s visual certainty, his crew faced technical unknowns.
From The Wall Street Journal ● Jul. 20, 2026
He steered himself with a certainty I found astounding.
From "Becoming" by Michelle Obama
These calculations are useful, but they are estimates rather than certainties.
From MarketWatch ● May 26, 2026
AI systems produce probabilities, and people treat them as certainties.
From Salon ● May 12, 2026
Death and taxes were certainties long before Benjamin Franklin made the observation in 1789.
From Barron's ● Apr. 14, 2026
He prided himself on having a mind unstained by certainties.
From Los Angeles Times ● Nov. 30, 2025
Chopin’s rich and ambiguous harmonies, interwoven intricately between the hands, looked to the future, leaving behind the primary-colour certainties of Gluck, Mozart, Haydn and early Beethoven once and for all.
From "The Story of Music" by Howard Goodall
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.