Most hackneyed (7)
I believe the answer is:
tritest
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">most hackneyed</span>' is the definition.<br/ ><span class="explanation-format__explanation">('trite' can be a synonym of 'hackneyed')</span><br/ ><br/ >This is the entire clue.<br/ ></span>
(Other definitions for tritest that I've seen before include "most worn-out" , "Most hackneyed" .)