Obscure, uncertain (7)
I believe the answer is:
unclear
<span class="explanation-format__ClueExplanation">This clue is a double definition.<br/ ><br/ >'<span class="explanation-format__original">obscure</span>' is the first definition.<br/ ><span class="explanation-format__explanation">(unclear can mean obscure or vague)</span><br/ ><br/ >'<span class="explanation-format__original">uncertain</span>' is the second definition.<br/ ><span class="explanation-format__explanation">(thesaurus)</span><br/ ><br/ ></span>
(Other definitions for unclear that I've seen before include "in clouds?" , "Ill-defined or not easily understood" , "Vague" , "hard to understand" , "Not distinct in nuclear way" .)