Meaning of Stirling's formula

Stir'ling's for'mula

Pronunciation: (stûr'lingz), [key]
— Math. Math.
  1. a relation that approximates the value of n factorial (n!), expressed as (n/e)2&pgr;n&fullradicover;.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.