Became better (8)
I believe the answer is:
improved
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">became better</span>' is the definition.<br/ ><span class="explanation-format__explanation">('improve' can be a synonym of 'become better')</span><br/ ><br/ >This is all the clue.<br/ ></span>
(Other definitions for improved that I've seen before include "Grew or made better" , "Made better in quality" , "Made progress" , "Made or got better" , "Became better" .)