Wonderful boss (5)
I believe the answer is:
super
This clue is a double definition.
'wonderful' is the first definition.
(I've seen this before)
'boss' is the second definition.
(thesaurus)
(Other definitions for super that I've seen before include "Delightful" , "Top" , "Gushily great, excellent" , "Prefix meaning over or extremely" , "Great; wonderful" .)