Quid pro quo
I believe the answer is:
swap
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">quid pro quo</span>' is the definition.<br/ ><span class="explanation-format__explanation">(synonyms)</span><br/ ><br/ >This is all the clue.<br/ ></span>
(Other definitions for swap that I've seen before include "Exchange; hands back" , "Fifty-fifty odds" , "exchanged gift" , "Switch" , "Exchange for paws" .)