Banger used by wise man going round America (7)
I believe the answer is:
sausage
'banger' is the definition.
(I know that sausage is a type of banger)
'wise man going round america' is the wordplay.
'wise man' becomes 'sage' (sage is a kind of wise man).
'going round' indicates putting letters inside (some letters go around others).
'america' becomes 'usa' (United States of America).
'sage' placed around 'usa' is 'SAUSAGE'.
'used by' is the link.
(Other definitions for sausage that I've seen before include "Minced meat product" , "Long, bagged meat product" , "Part of a hot dog" , "Minced meat and fat in cylindrical skin" , "Minced meat in a tube" .)