Bigwig (5)
I believe the answer is:
nabob
'bigwig' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for nabob that I've seen before include "Mogul governor; very rich or important person" , "Rich British merchant in India" , "Person of conspicuous wealth or high status" , "Fat cat: governor in India during the Mogul empire" , "Devotional painting" .)