Greedy pig, not very good, harsh (8)
I believe the answer is:
grasping
'greedy' is the definition.
('grasping' can be a synonym of 'greedy')
'good harsh' is the wordplay.
'good' becomes 'g' (abbreviation).
'harsh' becomes 'rasping' ('rasping' can be a synonym of 'harsh').
'g'+'rasping'='GRASPING'
'pig not very' is the link.
I am not very happy about this link. Some or all of it may belong to another bit of the clue.
(Other definitions for grasping that I've seen before include "avaricious attitude" , "Acquisitive - understanding" , "Holding" , "Gangs rip, being greedy" , "Miserly; seizing" .)