Go back with husband, a greedy fellow (3)
I believe the answer is:
hog
'a greedy fellow' is the definition.
(hog can mean a greedy person)
'go back with husband' is the wordplay.
'back' says the letters should be written in reverse.
'with' says to put letters next to each other.
'husband' becomes 'h'.
'go' back-to-front is 'og'.
'og' after 'h' is 'HOG'.
(Other definitions for hog that I've seen before include "Pig, who holds the road perhaps" , "Greedy person or pig for slaughter" , "Selfishly keep" , "Pig reared for slaughter" , "Gourmand" .)