Belittle; shrink (6)
I believe the answer is:
lessen
<span class="explanation-format__ClueExplanation">I believe this is a double definition.<br/ ><br/ >'<span class="explanation-format__original">belittle</span>' is the first definition.<br/ ><span class="explanation-format__explanation">(I've seen this in another clue)</span><br/ ><br/ >'<span class="explanation-format__original">shrink</span>' is the second definition.<br/ ><span class="explanation-format__explanation">(I've seen this before)</span><br/ ><br/ ></span>
(Other definitions for lessen that I've seen before include "Cut back or diminish" , "Make smaller for lenses" , "Make smaller or fewer" , "Become smaller or fewer" , "Abate" .)