Invigorate, revitalise (7)
I believe the answer is:
freshen
<span class="explanation-format__ClueExplanation">I believe this is a double definition.<br/ ><br/ >'<span class="explanation-format__original">invigorate</span>' is the first definition.<br/ ><span class="explanation-format__explanation">(thesaurus)</span><br/ ><br/ >'<span class="explanation-format__original">revitalise</span>' is the second definition.<br/ ><span class="explanation-format__explanation">(thesaurus)</span><br/ ><br/ ></span>
(Other definitions for freshen that I've seen before include "Re-invigorate" , "(Wind) get stronger" , "(Of wind) become stronger and colder" , "Make less stale" , "Grow stronger (wind)" .)