paluuvirtaus

Noun

 * 1) return flow any returning flow of a fluid
 * 2) undertow flow of water returning seaward from the waves breaking on the shore
 * 3) rip current particularly strong return flow of water from breaking waves, away from the shore, caused by underwater topology, which at some places concentrates the returning water into a powerful current

Usage notes
Strong undertow or rip currents are seldom seen along Finnish coastline (especially on such weather which would make the people want to swim!) and therefore the terminology regarding undersea currents is less developed than in some other languages. The word is sometimes used for "rip current" to separate it from "regular" return flow.