Broad, deep (5)
I believe the answer is:
thick
<span class="explanation-format__ClueExplanation">I believe this clue is a double definition.<br/ ><br/ >'<span class="explanation-format__original">broad</span>' is the first definition.<br/ ><span class="explanation-format__explanation">(associated in meaning)</span><br/ ><br/ >'<span class="explanation-format__original">deep</span>' is the second definition.<br/ ><span class="explanation-format__explanation">(I know that deep can be written as thick)</span><br/ ><br/ ></span>
(Other definitions for thick that I've seen before include "But surely not all thieves are" , "Broad; dense" , "Stupid; close-packed" , "having such a head?" , "unintelligent?" .)