Extravagant American leaving Sunshine State (6)
I believe the answer is:
florid
'extravagant' is the definition.
(thesaurus)
'american leaving sunshine state' is the wordplay.
'american' becomes 'a' (common abbreviation - e.g. in organisation names).
'leaving' is a deletion indicator.
'sunshine state' becomes 'florida' ('Florida' can be a synonym of 'sunshine state').
'florida' with 'a' taken out is 'FLORID'.
(Other definitions for florid that I've seen before include "Ruddy, flushed" , "Red-faced, flushed" , "With flushed complexion" , "Elaborately ornamented" , "Over-elaborate" .)