Be right in the south of Italy (3)
I believe the answer is:
fit
'be right' is the definition.
(I've seen this in another clue)
'in the south of italy' is the wordplay.
'in the south' suggests the final letters (I've seen 'in the south of' mean this (in a down clue, the bottom letter)).
'italy' becomes 'it'.
The last letter of 'of' is 'f'.
'f'+'it'='FIT'
(Other definitions for fit that I've seen before include "Adequate" , "In good physical shape 93)" , "Healthy; conform to" , "Attractive" , "Ready" .)