On the surface, skin-deep (11)
I believe the answer is:
superficial
<span class="explanation-format__ClueExplanation">This clue is a double definition.<br/ ><br/ >'<span class="explanation-format__original">on the surface</span>' is the first definition.<br/ ><span class="explanation-format__explanation">(thesaurus)</span><br/ ><br/ >'<span class="explanation-format__original">skin-deep</span>' is the second definition.<br/ ><span class="explanation-format__explanation">(similar in meaning)</span><br/ ><br/ ></span>
(Other definitions for superficial that I've seen before include "12 [TWO DIMENSIONAL]" , "Cursory" , "Not profound" , "Far from thorough" .)