Sick with greed, terribly worried (8)
I believe the answer is:
badgered
'worried' is the definition.
(thesaurus)
'sick with greed terribly' is the wordplay.
'sick' becomes 'bad' (similar in meaning).
'with' is an insertion indicator.
'terribly' indicates an anagram.
'greed' with letters rearranged gives 'dgere'.
'bad' going around 'dgere' is 'BADGERED'.
(Other definitions for badgered that I've seen before include "chivvied" , "hassled" , "Pestered" , "Harassed" , "Annoyed persistently" .)