Bow of a vessel (4)
I believe the answer is:
prow
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">bow of a vessel</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 prow that I've seen before include "Pointed front part of a ship" , "Front end of ship" , "(Ship's) bow" , "Ship's front part" , "bows" .)