Occurring between stars (12)
I believe the answer is:
interstellar
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">occurring between stars</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 interstellar that I've seen before include "Occurring between stars" , "In deep space" , "realm of Star Trek" .)