Flow back (3)
I believe the answer is:
ebb
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">flow back</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this before)</span><br/ ><br/ >This is all the clue.<br/ ></span>
(Other definitions for ebb that I've seen before include "Type of tide" , "Receding movement, as of a tide" , "(Water) recede" , "state of decline" , "Abate" .)