Gratifying (9)
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">gratifying</span>' is the definition.<br/ ><span class="explanation-format__explanation">(similar in meaning)</span><br/ ><br/ >This is all the clue.<br/ ></span>
(Other definitions for rewarding that I've seen before include "worthwhile" , "Satisfying, well worth doing" , "profitable" , "Providing personal satisfaction" , "Well worth doing for its own sake" .)