Factorial

Webster's Dictionary of the English Language

·adj Related to factorials.

II. Factorial ·adj Of or pertaining to a factory.

III. Factorial ·noun The product of the consecutive numbers from unity up to any given number.

IV. Factorial ·noun 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.