Owner (10)
I believe the answer is:
proprietor
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">owner</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I know that owner can be written as proprietor)</span><br/ ><br/ >This is the entire clue.<br/ ></span>
(Other definitions for proprietor that I've seen before include "Landlord" , "Business owner" .)