Not spotted (9)
I believe the answer is:
unnoticed
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">not spotted</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this in another clue)</span><br/ ><br/ >This is the entire clue.<br/ ></span>
(Other definitions for unnoticed that I've seen before include "Unperceived" , "Overlooked" , "Not registered" , "out of the public eye?" , "Continued to be unseen" .)