Fine belt delivered after American returned (6)
I believe the answer is:
subtle
'fine' is the definition.
(synonyms)
'belt delivered after american returned' is the wordplay.
I cannot quite see how this works, but
an anagram of 'belt' is 'btle' which is located in the answer.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for subtle that I've seen before include "Discriminatory" , "Understated, fine" , "Understated - discreetly clever" , "Not blatant" , "Very nice" .)