counterfactual

American  

[koun-ter-fak-choo-uhl] / ˌkaʊn tərˈfæk tʃu əl /

noun

Logic.

1. a conditional statement the first clause of which expresses something contrary to fact, as “If I had known.”

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counterfactual British  

/ ˌkauntəˈfæktʃʊəl /

adjective

1. expressing what has not happened but could, would, or might under differing conditions

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noun

1. a conditional statement in which the first clause is a past tense subjunctive statement expressing something contrary to fact, as in

   if she had hurried she would have caught the bus

Other Word Forms

• counterfact
  noun
• counterfactually
  adverb

Etymology

Origin of counterfactual

First recorded in 1945–50; counter- + factual

Example Sentences

See Examples For:

counterfactual

But every rule proposed today should be tested against a simple counterfactual: had it been on the books a decade ago, would the firm we are now regulating have ever been built?

From The Wall Street Journal ● Jul. 31, 2026

EEA studies compare an event's characteristics, such as its probability and intensity in the current climate, to a "counterfactual" world without human-caused emissions.

From Barron's ● Jul. 16, 2026

We can't be certain because the results depend heavily on the method chosen by researchers for measuring the "counterfactual", i.e what would have happened to UK exports had the country stayed in the EU.

From BBC ● Jan. 30, 2025

Overall, the counterfactual scenarios generate peak discharges at more than 70 per cent of the 516 river gauges across Germany considered in this study that exceed the record floods currently recorded there.

From Science Daily ● Mar. 27, 2024

For projects claiming to avoid emissions, it's difficult to prove the counterfactual: Would a given forest really have been cut down without the offset project?

From Salon ● Apr. 12, 2023