Sin or stray (3)
I believe the answer is:
err
<span class="explanation-format__ClueExplanation">I believe this is a double definition.<br/ ><br/ >'<span class="explanation-format__original">sin</span>' is the first definition.<br/ ><span class="explanation-format__explanation">(to sin is to err morally)</span><br/ ><br/ >'<span class="explanation-format__original">stray</span>' is the second definition.<br/ ><span class="explanation-format__explanation">(I know that stray can be written as err)</span><br/ ><br/ ></span>
(Other definitions for err that I've seen before include "Boob" , "'to... is human,to forgive divine'" , "Sin" , "Make mistakes" , "Make mistake in Canberra" .)