Encroach, force upon (6)
I believe the answer is:
impose
<span class="explanation-format__ClueExplanation">I believe this clue is a double definition.<br/ ><br/ >'<span class="explanation-format__original">encroach</span>' is the first definition.<br/ ><span class="explanation-format__explanation">(thesaurus)</span><br/ ><br/ >'<span class="explanation-format__original">force upon</span>' is the second definition.<br/ ><span class="explanation-format__explanation">(I've seen this before)</span><br/ ><br/ ></span>
(Other definitions for impose that I've seen before include "Force (on someone)" , "Decree" , "Obtrude, force (on)" , "Put upon, say a tax" , "Levy or force upon" .)