noun

1. ☆
   1. a shoal, reef, or shallow in a stream, producing a stretch of ruffled or choppy water
   2. a stretch of such water
   3. a ripple or the ripples of such water
2. 1. a contrivance, as of bars or slats, put across the bottom of a sluice to form grooves or open spaces for catching and holding particles of gold in mining
   2. any of the bars, slats, etc.
   3. any of the grooves or spaces
3. the act or a manner of riffling cards

Etymology: < ? or akin to Ger riffel, groove, furrow < EFris, akin to OE rifelung, wrinkle < IE base *rei-, to tear > reap

transitive verb, intransitive verb riffled -·fled, riffling -·fling

1. to form, become, or flow over or through, a riffle
2. to leaf rapidly through (a book, etc.), as by letting the edges or corners of the pages slip lightly across the thumb
3. to shuffle (playing cards) by holding part of the deck in each hand, raising the corners or edges slightly, and causing the cards to fall alternately together

Etymology: < ? Ger riffeln, to form riffles, groove: see rifflethe