Most comprehensive (8)
I believe the answer is:
broadest
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">most comprehensive</span>' is the definition.<br/ ><span class="explanation-format__explanation">('broad' can be similar in meaning to 'comprehensive')</span><br/ ><br/ >This is the entire clue.<br/ ></span>
(Other definitions for broadest that I've seen before include "Most unspecific" , "Most general, extensive" , "Widest" .)