Factorial meaning : The result of multiplying a given number of consecutive integers from 1 to the given number. In equations, it is symbolized by an exclamation mark (!). For example, 5! = 1 × 2 × 3 × 4 × 5 = 120. Of or pertaining to a factor or factorial. Of or pertaining to a factor, a kind of business agent. Of or pertaining to a factory.