Row about good animal (5)
I believe the answer is:
tiger
'animal' is the definition.
(tiger is a type of animal)
'row about good' is the wordplay.
'row' becomes 'tier' (a tier is a row of things).
'about' is an insertion indicator.
'good' becomes 'g' (abbreviation).
'tier' placed around 'g' is 'TIGER'.
(Other definitions for tiger that I've seen before include "Carnivorous large cat" , "The Celtic one has died" , "Beast - type of 1 across" , "Dangerous animal" , "Large wild cat" .)