Interfering, I gutted dead fish (8)
I believe the answer is:
meddling
'interfering' is the definition.
(I know that interfering can be written as meddling)
'i gutted dead fish' is the wordplay.
'i' becomes 'me'.
'gutted' says to hollow out the word (remove centre letters) (to gut something is to remove its insides).
'fish' becomes 'ling' (ling is a kind of fish).
'dead' with its centre taken out is 'dd'.
'me'+'dd'+'ling'='MEDDLING'
(Other definitions for meddling that I've seen before include "Interference" , "Interfering unnecessarily" , "Interfering in someone else's business" , "Interfering, intruding" , "Interfering in matters not one's business." .)