riffle
noun
°A fast-flowing, shallow part of a stream.
°A trough or sluice having cleats, grooves, or steps across the bottom for holding quicksilver and catching particles of gold when auriferous earth is washed. Also one of the cleats, grooves or steps in such trough.
verb
°To ruffle with a rippling action.
°To skim or flick through the pages of a book.