Overly (3)
I believe the answer is:
too
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">overly</span>' is the definition.<br/ ><span class="explanation-format__explanation">(synonyms)</span><br/ ><br/ >This is all the clue.<br/ ></span>
(Other definitions for too that I've seen before include "What a pity!" , "Likewise" , "Excessively" , "Moreover, in addition" , "As well, also" .)