Knave, scamp (6)
I believe the answer is:
rascal
<span class="explanation-format__ClueExplanation">I believe this clue is a double definition.<br/ ><br/ >'<span class="explanation-format__original">knave</span>' is the first definition.<br/ ><span class="explanation-format__explanation">(synonyms)</span><br/ ><br/ >'<span class="explanation-format__original">scamp</span>' is the second definition.<br/ ><span class="explanation-format__explanation">(synonyms)</span><br/ ><br/ ></span>
(Other definitions for rascal that I've seen before include "Mischievous or cheeky person" , "naughty child" , "Mischievous fellow" , "Rogue or cheeky child" , "Rogue of a lascar" .)