Tosses in (4)
I believe the answer is:
adds
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">tosses in</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this in another clue)</span><br/ ><br/ >This is all the clue.<br/ ></span>
(Other definitions for adds that I've seen before include "Contributes further" , "Finds the sum (4)," , "Aggregates or appends" , "Puts (numbers) together" , "Calculates the sum" .)