Apathetic, careless (13)
I believe the answer is:
lackadaisical
<span class="explanation-format__ClueExplanation">I believe this is a double definition.<br/ ><br/ >'<span class="explanation-format__original">apathetic</span>' is the first definition.<br/ ><span class="explanation-format__explanation">(I've seen this before)</span><br/ ><br/ >'<span class="explanation-format__original">careless</span>' is the second definition.<br/ ><span class="explanation-format__explanation">(I've seen this before)</span><br/ ><br/ ></span>
(Other definitions for lackadaisical that I've seen before include "Languid and ineffectual" , "Carelessly lazy" , "Listless" , "Half-hearted" , "Spiritless" .)