Unnamed
I believe the answer is:
anonymous
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">unnamed</span>' is the definition.<br/ ><span class="explanation-format__explanation">(similar in meaning)</span><br/ ><br/ >This is all the clue.<br/ ></span>
(Other definitions for anonymous that I've seen before include "Incognito" , "Unidentified" , "Not identified by name" , "Of unknown identity" , "Having no known name" .)