Vietnam's neighbor (4)
I believe the answer is:
laos
'vietnam's neighbor' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for laos that I've seen before include "Republic in southeastern Asia" , "Asian country, capital Vientiane" , "Landlocked state in southeastern Asia" , "Republic of southeast Asia" , "part of Asia" .)