Place side by side (9)
I believe the answer is:
juxtapose
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">place side by side</span>' is the definition.<br/ ><span class="explanation-format__explanation">(synonyms)</span><br/ ><br/ >This is all the clue.<br/ ></span>
(Other definitions for juxtapose that I've seen before include "Place nearby" , "Place alongside for comparison" , "Place adjacently" , "Put side by side" , "put together" .)