Norwegian inlets of the sea (6)
I believe the answer is:
fjords
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">norwegian inlets of the sea</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 fjords that I've seen before include "More than one Channel" , "Scandinavian inlets" , "Rock-bound inlets" , "rocky inlets" , "Long narrow sea inlets between steep cliffs in Norway" .)