Definition of factorial noun from the Oxford Advanced American Dictionary

 

factorial

 noun
noun
NAmE//fækˈtɔriəl//
 
(mathematics)
 
jump to other results
the result when you multiply a whole number by all the numbers below it factorial 5 (represented as 5!) = 5 × 4 × 3 × 2 × 1
See the Oxford Advanced Learner's Dictionary entry: factorial