Demarcate (6)
I believe the answer is:
define
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">demarcate</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this in another clue)</span><br/ ><br/ >This is all the clue.<br/ ></span>
(Other definitions for define that I've seen before include "Give the meaning or mark the limits of" , "Explain the meaning of a word" , "Describe exactly" , "Fix the meaning of" , "Specify" .)