'Factorial' definitions:

Definition of 'factorial'

(from WordNet)
adjective
Of or relating to factorials
noun
The product of all the integers up to and including a given integer; "1, 2, 6, 24, and 120 are factorials"

Definition of 'Factorial'

From: GCIDE
  • Factorial \Fac*to"ri*al\, n. (Math.) (a) pl. A name given to the factors of a continued product when the former are derivable from one and the same function F(x) by successively imparting a constant increment or decrement h to the independent variable. Thus the product F(x).F(x + h).F(x + 2h) . . . F[x + (n-1)h] is called a factorial term, and its several factors take the name of factorials. --Brande & C. (b) The product of the consecutive whole numbers from unity up to any given number; thus, 5 factorial is the product of 5 times four times three times two times one, or 120. [1913 Webster +PJC]

Definition of 'Factorial'

From: GCIDE
  • Factorial \Fac*to"ri*al\, a.
  • 1. Of or pertaining to a factory. --Buchanan. [1913 Webster]
  • 2. (Math.) Related to factorials. [1913 Webster]