Mideast bigwig (4)
I believe the answer is:
emir
'mideast bigwig' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for emir that I've seen before include "Ruler or chieftain in Arabia" , "Islamic chieftain" , "Arab ruler" , "Arab chieftain" , "Title of various rulers; I'm ER (anag.)" .)