Cut off from the sea (10)
I believe the answer is:
landlocked
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">cut off from 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 landlocked that I've seen before include "Cut off from the sea" , "like the Swiss?" , "With no sea coast" .)