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

Nothing in life is guaranteed, but as near a 100 per cent certainty as there can be among Premier League managers. — Jacob Tanswell, New York Times, 19 Aug. 2026

Stevie Ringel Ringel launched the Kizuna Foundation, and was able to raise money towards developing an individualized treatment, but the work required to get there, coupled with a lack of certainty around the process, was taxing. — Brad Quick, CNBC, 18 Aug. 2026

Senior leaders typically face enormous pressure to project certainty. — Dev Patnaik, Forbes.com, 18 Aug. 2026

Another collision at some point is a certainty, says Stijn Lemmens, a space debris analyst at the European Space Agency. — Jonathan O'Callaghan, Scientific American, 18 Aug. 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