Passport (4)
I believe the answer is:
visa
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">passport</span>' is the definition.<br/ ><span class="explanation-format__explanation">(thesaurus)</span><br/ ><br/ >This is all the clue.<br/ ></span>
(Other definitions for visa that I've seen before include "Travel warrant" , "Endorsement made in a passport" , "It allows the bearer to enter the country issuing it" , "Stamp affixed to passport as permission to enter country" , "ID" .)