Have command over (8)
I believe the answer is:
dominate
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">have command over</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this before)</span><br/ ><br/ >This is the entire clue.<br/ ></span>
(Other definitions for dominate that I've seen before include "Look down on; have control over" , "Tower over" , "Command, control" , "Admit one in order to be in control" , "Govern" .)