Third planet from the sun (5)
I believe the answer is:
earth
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">third planet from the sun</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 earth that I've seen before include "dirt" , "hideaway" , "cost of which is very high" , "Third planet from the Sun" , "underground shelter" .)