Warmed up (6)
I believe the answer is:
heated
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">warmed up</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this before)</span><br/ ><br/ >This is the entire clue.<br/ ></span>
(Other definitions for heated that I've seen before include "Made warm" , "Angry, impassioned" , "Inflamed with passion" , "Fired-up" , "Vehement" .)