Copious, abundant (5)
I believe the answer is:
ample
<span class="explanation-format__ClueExplanation">I believe this is a double definition.<br/ ><br/ >'<span class="explanation-format__original">copious</span>' is the first definition.<br/ ><span class="explanation-format__explanation">(synonyms)</span><br/ ><br/ >'<span class="explanation-format__original">abundant</span>' is the second definition.<br/ ><span class="explanation-format__explanation">(similar in meaning)</span><br/ ><br/ ></span>
(Other definitions for ample that I've seen before include "Sealed glass container for dose of medicine" , "Big" , "Fairly large" , "Plenty, more than enough" , "Plenteous" .)