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
• 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

In a world where the only certainty is change, agility isn't just an advantage. —Elaine Pulakos, Forbes.com, 2 July 2025

That certainty dampens any excitement to find out what happens to her next. —Rafaela Bassili, Vulture, 2 July 2025

Our certainty on that, however, is diminished by Boeser extending. —Harman Dayal, New York Times, 1 July 2025

Family businesses have been waiting impatiently for certainty on tax policy, as many of the 2017 improvements in the Tax Cuts and Jobs Act were made temporary to fit within the Senate’s arcane budget reconciliation restrictions. —Palmer Schoening, Boston Herald, 27 June 2025

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