Copy American training (3)
I believe the answer is:
ape
'copy' is the definition.
('ape' can be a synonym of 'copy')
'american training' is the wordplay.
'american' becomes 'a' (common abbreviation - e.g. in organisation names).
'training' becomes 'pe' (**).
'a'+'pe'='APE'
(Other definitions for ape that I've seen before include "Mimic the primate" , "Idiot" , "Send up" , "Simian - copy" , "drill" .)