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 of certainty

• assurance
• confidence
• satisfaction
• conviction

Choose the Right Synonym for certainty

certainty, certitude, conviction 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

while certitude may emphasize a faith in something not needing or not capable of proof.

believes with certitude in an afterlife

conviction applies especially to belief strongly held by an individual.

holds firm convictions on every issue

Examples of certainty in a Sentence

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

When questioned by officers, the woman could not say with certainty how long the attack lasted, but a law enforcement source said the suspect held the woman against her will for hours. —Nicholas Williams, New York Daily News, 14 June 2026

Fiction can be tempting when facts prove elusive, and Tannahill’s series cherishes dancing between the demanding allure of the unknown and the fearful certainty of what can happen when pursuing it. —Ben Travers, IndieWire, 12 June 2026

That means faster permitting, reliable leasing, support for pipelines and ports, regulatory certainty for LNG terminals and a policy environment that encourages long-term investment. —Dan Eberhart, Forbes.com, 12 June 2026

Recall those hundred or so volunteers who put their own bodies on the line to advance the possibility—absolutely not the certainty—of eliminating a brutal scourge, HIV/AIDS. —Literary Hub, 11 June 2026

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

• almost a certainty
• with certainty

Rhymes for certainty

• uncertainty

Kids Definition

certainty

noun

cer·​tain·​ty ˈsərt-ᵊn-tē 

plural certainties

1

: something certain

2

: the quality or state of being or feeling certain