Charge American a pound, placed on account (7)
I believe the answer is:
accusal
'charge' is the definition.
(accusal is a kind of charge)
'american a pound placed on account' is the wordplay.
'american' becomes 'usa'.
'a pound' becomes 'l'.
'placed on' means one lot of letters go next to another.
'account' becomes 'acc'.
'usa'+'l'='usal'
'usal' after 'acc' is 'ACCUSAL'.
(Other definitions for accusal that I've seen before include "Act of imputing blame or guilt" , "Indictment" , "Formal charge of wrongdoing" .)