Nautical map (5)
I believe the answer is:
chart
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">nautical map</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 chart that I've seen before include "Table or graph" , "Visual display of information" , "Nautical map" , "Plan" , "Navigational map" .)