certainty
noun
cer·tain·ty ˈsər-tᵊn-tē 
plural certainties
1
: something that is certain
2
: the quality or state of being certain especially on the basis of evidence
Synonyms
- assurance
- assuredness
- certitude
- cocksureness
- confidence
- conviction
- doubtlessness
- face
- positiveness
- satisfaction
- sureness
- surety
See all Synonyms & Antonyms 
Example Sentences
Scientists still do not know with any degree of certainty why the disease spread so quickly. We cannot predict the outcome with absolute certainty. There was no certainty that the package would arrive in time. Her certainty about these complex moral issues is surprising.
Recent Examples on the Web Despite that, medical experts still can’t say with certainty how drug use affects developing fetuses. 
al, 1 Sep. 2022 The number isn't known with certainty because fawns continue to be born at the site. Paul A. Smith, USA TODAY, 26 July 2022 Unlike a digital system, where a bit can be flipped from a one to a zero with certainty, a quantum computer operates in an analog world. Chris Lee, Ars Technica, 25 July 2022 The number isn't known with certainty because fawns continue to be born at the site. Paul A. Smith, Journal Sentinel, 23 July 2022 Months in advance, the United States knew with certainty that Putin was planning an all-out invasion of Ukraine. Robert Zubrin, National Review, 23 July 2022 Predicting with certainty which ones, if any, will go, or when, is impossible. Faith Hill, The Atlantic, 1 July 2022 Officials and experts in California cannot say with certainty why the state’s increasing coronavirus case rates have not translated into larger numbers of hospitalizations, leaving the state in a much better spot than the East Coast. Los Angeles Times, 23 May 2022 Convictions had seemed a certainty because of the powerful evidence of the videotape and the fact that the Los Angeles Police Department’s top expert on excessive force testified against the officers. San Diego Union-Tribune, 2 May 2022 See More
al, 1 Sep. 2022 The number isn't known with certainty because fawns continue to be born at the site. Paul A. Smith, USA TODAY, 26 July 2022 Unlike a digital system, where a bit can be flipped from a one to a zero with certainty, a quantum computer operates in an analog world. Chris Lee, Ars Technica, 25 July 2022 The number isn't known with certainty because fawns continue to be born at the site. Paul A. Smith, Journal Sentinel, 23 July 2022 Months in advance, the United States knew with certainty that Putin was planning an all-out invasion of Ukraine. Robert Zubrin, National Review, 23 July 2022 Predicting with certainty which ones, if any, will go, or when, is impossible. Faith Hill, The Atlantic, 1 July 2022 Officials and experts in California cannot say with certainty why the state’s increasing coronavirus case rates have not translated into larger numbers of hospitalizations, leaving the state in a much better spot than the East Coast. Los Angeles Times, 23 May 2022 Convictions had seemed a certainty because of the powerful evidence of the videotape and the fact that the Los Angeles Police Department’s top expert on excessive force testified against the officers. San Diego Union-Tribune, 2 May 2022 See More Word History
Etymology
Middle English certeinte, borrowed from Anglo-French certeinté, from certein, certain certain entry 1 + -té -ty
First Known Use
14th century, in the meaning defined at sense 1
Phrases Containing certainty
Kids Definition
certainty
noun
cer·tain·ty ˈsər-tᵊn-tē
plural certainties
1
: something that is sure
Victory was a certainty.
2
: the quality or state of being sure
She answered with certainty.
certainty
noun
1
as in assurance
a state of mind in which one is free from doubt I have full certainty that I'll pass the test Synonyms & Similar Words
Relevance
- assurance
- confidence
- satisfaction
- conviction
- certitude
- assuredness
- sureness
- surety
- positiveness
- cocksureness
- doubtlessness
- determination
- dogmatism
- face
- authoritarianism
- decisiveness
- firmness
- resolve
- purposefulness
- resolution
- resoluteness
Antonyms & Near Antonyms
- uncertainty
- doubt
- hesitation
- hesitancy
- irresolution
- incertitude
- concern
- disbelief
- incredulity
- anxiety
- indecisiveness
- unbelief
- nonconfidence
- suspicion
- distrust
- misgiving
- mistrust
2
as in likelihood
the quality or state of being impossible to avoid or evade the proverbial certainty of death and taxes Synonyms & Similar Words
- likelihood
- inevitability
- inevitableness
- probability
- inexorability
- ineluctability
- inexorableness
- relentlessness
Antonyms & Near Antonyms
- uncertainty
- improbability
- unlikelihood
- preventability
- doubtfulness
- dubiousness
- unlikeliness
Synonym Chooser
The words certitude and conviction are common synonyms of certainty. While all three words mean "a state of being free from doubt," certainty and certitude are very close; certainty may stress the existence of objective proof.
claims that cannot be confirmed with scientific certainty
The synonyms certitude and certainty are sometimes interchangeable, but certitude may emphasize a faith in something not needing or not capable of proof.
believes with certitude in an afterlife
In some situations, the words conviction and certainty are roughly equivalent. However, conviction applies especially to belief strongly held by an individual.
holds firm convictions on every issue