Indecent, unseemly (8)
I believe the answer is:
improper
<span class="explanation-format__ClueExplanation">I believe this clue is a double definition.<br/ ><br/ >'<span class="explanation-format__original">indecent</span>' is the first definition.<br/ ><span class="explanation-format__explanation">(associated in meaning)</span><br/ ><br/ >'<span class="explanation-format__original">unseemly</span>' is the second definition.<br/ ><span class="explanation-format__explanation">(similar in meaning)</span><br/ ><br/ ></span>
(Other definitions for improper that I've seen before include "unfit" , "Wrong - unsuitable" , "'Not suitable, right or appropriate (8)'" , "Incorrect or wrong, say behaviour" , "Unseemly, indelicate" .)