Saturn's largest moon (5)
I believe the answer is:
titan
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">saturn's largest moon</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 titan that I've seen before include "Atlas, say" , "primordial god" , "One of elder gods defeated by Zeus" , "Mythological giant" , "Giant god of Greek myth" .)