Proprietor (5)
I believe the answer is:
owner
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">proprietor</span>' is the definition.<br/ ><span class="explanation-format__explanation">(synonyms)</span><br/ ><br/ >This is all the clue.<br/ ></span>
(Other definitions for owner that I've seen before include "Title holder?" , "Title-holder" , "Man of property" , "One who has something" , "Keeper" .)