Be plentiful (6)
I believe the answer is:
abound
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">be plentiful</span>' is the definition.<br/ ><span class="explanation-format__explanation">(synonyms)</span><br/ ><br/ >This is all the clue.<br/ ></span>
(Other definitions for abound that I've seen before include "On a bud (anag)" , "Be plentiful, be present on great quantities" , "Be prolific" , "Exist in large numbers" , "Exist plentifully" .)