riffle shuffle

Noun

 * 1)  A technique of shuffling a deck of playing cards by first separating the deck into two parts.
 * 2)  A permutation that models the outcome of a riffle shuffle; the operation of dividing an ordered set into two equal subsets and then alternately listing sequences of elements from each subset that have a common specified length.

Verb

 * 1)  To perform a riffle shuffle.