Georgia had resistance from fish (3)
I believe the answer is:
gar
'fish' is the definition.
(gar is a kind of fish)
'georgia had resistance' is the wordplay.
'georgia' becomes 'ga'.
'had' means one lot of letters go next to another.
'resistance' becomes 'r' (abbreviation).
'ga'+'r'='GAR'
'from' acts as a link.
(Other definitions for gar that I've seen before include "Creature" , "something fishy here" , "A fish; cloth scrap (reversed)" , "Pike-like fish" , "swimmer" .)