Definition (5)
I believe the answer is:
focus
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">definition</span>' is the definition.<br/ ><span class="explanation-format__explanation">(thesaurus)</span><br/ ><br/ >This is all the clue.<br/ ></span>
(Other definitions for focus that I've seen before include "Maximum clarity of an idea" , "Hub" , "Concentration of attention or energy" , "Cynosure" , "Concentrate the vision" .)