Cruel; unfeeling (9)
I believe the answer is:
heartless
<span class="explanation-format__ClueExplanation">This clue is a double definition.<br/ ><br/ >'<span class="explanation-format__original">cruel</span>' is the first definition.<br/ ><span class="explanation-format__explanation">(similar in meaning)</span><br/ ><br/ >'<span class="explanation-format__original">unfeeling</span>' is the second definition.<br/ ><span class="explanation-format__explanation">(I've seen this in another clue)</span><br/ ><br/ ></span>
(Other definitions for heartless that I've seen before include "Without pity or feeling, being defective in cardiac way" , "Cold-blooded" , "Unkind" , "with no concern for others?" , "Uncaring" .)