Star system (6)
I believe the answer is:
galaxy
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">star system</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 galaxy that I've seen before include "Lots of stars" , "Large star system" , "Huge collection of stars" , "Assemblage of stars" , "Division of the universe" .)