Breaking waves (4)
I believe the answer is:
surf
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">breaking waves</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this before)</span><br/ ><br/ >This is the entire clue.<br/ ></span>
(Other definitions for surf that I've seen before include "It's created by breaking waves" , "Breaking sea" , "Waves breaking on the shore" , "Balance on waves" , "Seashore foam" .)