Indefinite, unclear (8)
I believe the answer is:
nebulous
<span class="explanation-format__ClueExplanation">I believe this is a double definition.<br/ ><br/ >'<span class="explanation-format__original">indefinite</span>' is the first definition.<br/ ><span class="explanation-format__explanation">(similar in meaning)</span><br/ ><br/ >'<span class="explanation-format__original">unclear</span>' is the second definition.<br/ ><span class="explanation-format__explanation">(thesaurus)</span><br/ ><br/ ></span>
(Other definitions for nebulous that I've seen before include "Cloudy and vague" , "Indistinct and vague" , "'Cloudy, lacking definite form (8)'" , "Vague, lacking a distinct shape" , "Hazy, vague" .)