Get too big (for) (7)
I believe the answer is:
outgrow
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">get too big for</span>' is the definition.<br/ ><span class="explanation-format__explanation">(to outgrow something is to get too big for it)</span><br/ ><br/ >This is all the clue.<br/ ></span>
(Other definitions for outgrow that I've seen before include "Get bigger" , "Become too big for" , "excel in development" , "Become too large or too mature for" , "Develop beyond" .)