Under-the-counter (7)
I believe the answer is:
illegal
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">under-the-counter</span>' is the definition.<br/ ><span class="explanation-format__explanation">(similar in meaning)</span><br/ ><br/ >This is the entire clue.<br/ ></span>
(Other definitions for illegal that I've seen before include "Ignoring certain acts" , "Prohibited by law" , "Not lawful" , "Contrary to law" , "Criminal, illicit" .)