# factorial

[ fak-tawr-ee-uh l, -tohr- ]

/ fækˈtɔr i əl, -ˈtoʊr- /

### noun

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

### adjective

## Nearby words

factor x, factor xi, factor xii, factor xiii, factorage, factorial, factorial experiment, factorially, factoring, factorize, factory

Related formsfac·to·ri·al·ly, adverb

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Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

## British Dictionary definitions for factorially

## factorial

/ (fækˈtɔːrɪəl) maths /

### noun

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

### adjective

of or involving factorials or factors

Derived Formsfactorially, adverb

Collins English Dictionary - Complete & Unabridged 2012 Digital Edition
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## Word Origin and History for factorially

Online Etymology Dictionary, © 2010 Douglas Harper

## Science definitions for factorially

## factorial

[ făk-tôr′ē-əl ]

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 X 2 X 3 X 4, or 24.

The American Heritage® Science Dictionary
Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.