Feign, affect (9)
I believe the answer is:
dissemble
<span class="explanation-format__ClueExplanation">This clue is a double definition.<br/ ><br/ >'<span class="explanation-format__original">feign</span>' is the first definition.<br/ ><span class="explanation-format__explanation">(synonyms)</span><br/ ><br/ >'<span class="explanation-format__original">affect</span>' is the second definition.<br/ ><span class="explanation-format__explanation">(I know that affect can be written as dissemble)</span><br/ ><br/ ></span>
(Other definitions for dissemble that I've seen before include "Conceal one's true feelings" , "Disguise one's true feelings" , "Hide true motives" , "Hide one's true feelings" , "Conceal or disguise feelings or motives" .)