factorial

American  

[fak-tawr-ee-uhl, -tohr-] / fækˈtɔr i əl, -ˈtoʊr- /

noun

1. Mathematics. the product of a given positive integer multiplied by all lesser positive integers: The quantity four factorial (4!) = 4 ⋅ 3 ⋅ 2 ⋅ 1 = 24. n!, where n is the given integer.

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adjective

1. Mathematics. of or relating to factors or factorials.

2. of or relating to a factor or a factory.

factorial British  

/ fækˈtɔːrɪəl /

noun

1. the product of all the positive integers from one up to and including a given integer. Factorial zero is assigned the value of one: factorial four is 1 × 2 × 3 × 4 . Symbol: n !, where n is the given integer

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adjective

1. of or involving factorials or factors

factorial Scientific  

/ făk-tôr′ē-əl /

1. The product of all of the positive integers from 1 to a given positive integer. It is written as the given integer followed by an exclamation point. For example, the factorial of 4 (written 4!) is 1 × 2 × 3 × 4, or 24.

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Other Word Forms

• factorially
  adverb

Etymology

Origin of factorial

First recorded in 1810–20; factor + -ial

Example Sentences

Factorial is betting that companies want platforms with few specialized AI agents to better oversee their operations as opposed to software suites filled with all sorts of agents.

From The Wall Street Journal • Jun. 3, 2026

Founded in 2016, Factorial developed a platform for human resources, finance and tech teams, initially banking on a model known as software-as-a-service for which companies charge clients who subscribe to a platform or other service.

From The Wall Street Journal • Jun. 3, 2026

Auto giants such as Stellantis, which owns Ram and Jeep, are lavishing cash on startups such as Factorial Energy, which has fewer than 100 employees in an office park in Woburn, near Boston.

From Seattle Times • Mar. 13, 2022

Eventually, Factorial, which Mercedes and Hyundai have also invested in, wants to build factories around the world — an ambitious goal considering the company just moved into a second floor.

From New York Times • Mar. 7, 2022

Mercedes-Benz, part of Daimler AG, said it is joining forces with Factorial, based in Woburn, Massachussetts, to jointly develop batteries with the aim of testing prototype cells as early as next year.

From Seattle Times • Nov. 30, 2021