Huge destructive waves (8)

I believe the answer is:
tsunamis
'huge destructive waves' is the definition.
(I've seen this before)
This is all the clue.
(Other definitions for tsunamis that I've seen before include "Huge destructive waves" , "Violent sea waves" , "Destructive sea waves" , "Large ocean waves caused by underwater earthquakes" , "catastrophes" .)