Geometric mean
The Geometric Mean is the nth root of the product of n numbers. It is analogous to the Arithmetic Mean, except with products. For example, if I wanted to find the Geometric Mean of 2, 4, and 8, I would compute the cube root of 2*4*8=64, which is 4.
The Geometric Mean is a component of the well-known Arithmetic Mean-Geometric Mean Inequality.