Crosswise on deck (5)
I believe the answer is:
abeam
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">crosswise on deck</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this in another clue)</span><br/ ><br/ >This is the entire clue.<br/ ></span>
(Other definitions for abeam that I've seen before include "across width of ship" , "neither fore nor aft?" , "To the right or left of the centre of the ship" , "across the deck" , "At right-angles to keel" .)