Turkmenistan neighbor (4)
I believe the answer is:
iran
'turkmenistan neighbor' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for iran that I've seen before include "Persia today" , "Tehran is its capital" , "It used to be Persia" , "Middle East country" , "Farsi-speaking country" .)