From Longman Dictionary of Contemporary Englishrapidsrap‧ids /ˈræpədz/ noun [plural] DNpart of a river where the water looks white because it is moving very fast over rocks
Examples from the Corpus
rapids• Odd words and phrases came to him but, like sticks dropped into rapids, they were quickly whisked away.• The Tuolumne is where many rafters get baptized by the cool, clear and pounding rapids.• He suggested a stroll toward the three half-submerged rocks in the rapids known as the Three Sisters.• Ron - trapped inside - became part of the rapids, with the freezing white water breaking completely over him.• He became famous for canoeing down the Colorado and shooting the rapids.• The rapids was bookended by cliffs; there was no way to portage and no way to line.• Stephen Murray died after getting trapped under rocks when he fell from a raft going through rapids. 