Impulsive, fickle (10)
I believe the answer is:
capricious
<span class="explanation-format__ClueExplanation">I believe this clue is a double definition.<br/ ><br/ >'<span class="explanation-format__original">impulsive</span>' is the first definition.<br/ ><span class="explanation-format__explanation">(I know that impulsive can be written as capricious)</span><br/ ><br/ >'<span class="explanation-format__original">fickle</span>' is the second definition.<br/ ><span class="explanation-format__explanation">(thesaurus)</span><br/ ><br/ ></span>
(Other definitions for capricious that I've seen before include "Arbitrary and inconsistent" , "on a whim" , "Given to sudden mood swings" , "Changeable in mood" .)