rip·tide /ˈrɪpˌtaɪd/
洪濤,急流,激流
riptide
n 1: a stretch of turbulent water in a river or the sea caused by
one current flowing into or across another current [syn:
rip, tide rip, crosscurrent, countercurrent]
2: a strong surface current flowing outwards from a shore [syn:
rip current]