Joe North's spirit (3)
I believe the answer is:
gin
'spirit' is the definition.
(alcoholic spirit)
'joe north's' is the wordplay.
'joe' becomes 'GI' (GI Joe).
'north' becomes 'N' (abbreviation).
'gi'+'n'='GIN'
(Other definitions for gin that I've seen before include "Spirit; trap" , "Juniper-flavoured drink" , "game of cards" , "Alcoholic drink once known as mother's ruin" , "It often gets mixed up with this" .)