Neighbor of Vietnam (4)
I believe the answer is:
laos
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">neighbor of vietnam</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this in another clue)</span><br/ ><br/ >This is the entire clue.<br/ ></span>
(Other definitions for laos that I've seen before include "Mountainous state in southeastern Asia" , "Country between Thailand/Vietnam" , "Indo-Chinese country" , "Republic in southeastern Asia" , "SE Asian country" .)