SINCE 1828
factorial
adjective
fac·to·ri·al
| \ fak-ˈtȯr-ē-əl
\
\
Definition of factorial
(Entry 1 of 2)
: of, relating to, or being a factor or a factorial
factorial
nounDefinition of factorial (Entry 2 of 2)
1
: the product of all the positive integers from 1 to n
—symbol n!
2
: the quantity 0! arbitrarily defined as equal to 1
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