DuckCorp Dico

Found one definition

1.                 From WordNet (r) 3.0 (2006):
                   
   
   
                   
                     
   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, riptide, tide rip, crosscurrent,
            countercurrent]
       2: a strong surface current flowing outwards from a shore [syn:
          riptide, rip current]