Narrow waterways (7)
I believe the answer is:
straits
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">narrow waterways</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this in another clue)</span><br/ ><br/ >This is all the clue.<br/ ></span>
(Other definitions for straits that I've seen before include "Sea passages" , "Difficulties" , "... of Magellan, Hormuz" , "Dire --, rock band" , "Narrow channels of the sea joining two larger bodies of water" .)