Quadruple (8)
I believe the answer is:
fourfold
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">quadruple</span>' is the definition.<br/ ><span class="explanation-format__explanation">(synonyms)</span><br/ ><br/ >This is the entire clue.<br/ ></span>
(Other definitions for fourfold that I've seen before include "Quadruple" , "(Increased) with an addition of 300%" .)