American and English exploit (3)
I believe the answer is:
use
'exploit' is the definition.
(use can mean to exploit)
'american and english' is the wordplay.
'american' becomes 'us' (abbreviation for United States).
'and' says to put letters next to each other.
'english' becomes 'e' (abbreviation).
'us'+'e'='USE'
(Other definitions for use that I've seen before include "Sue for employment" , "consume; exploit" , "Employ or exploit" , "Employ - advantage" , "Consume; deploy" .)