Intensify, aggravate (7)
I believe the answer is:
inflame
<span class="explanation-format__ClueExplanation">I believe this is a double definition.<br/ ><br/ >'<span class="explanation-format__original">intensify</span>' is the first definition.<br/ ><span class="explanation-format__explanation">(thesaurus)</span><br/ ><br/ >'<span class="explanation-format__original">aggravate</span>' is the second definition.<br/ ><span class="explanation-format__explanation">(I know this)</span><br/ ><br/ ></span>
(Other definitions for inflame that I've seen before include "Make (a situation) worse" , "Intensify, aggravate" , "Provoke to anger" , "Excite passionate feelings" , "Exacerbate" .)