American with charming accent (5)
I believe the answer is:
acute
'accent' is the definition.
(acute accent is a kind of accent)
'american with charming' is the wordplay.
'american' becomes 'a' (common abbreviation - e.g. in organisation names).
'with' says to put letters next to each other.
'charming' becomes 'cute' (I've seen this in other clues).
'a'+'cute'='ACUTE'
(Other definitions for acute that I've seen before include "Sharp, angle or mind" , "Sharp-pointed - keenly perceptive" , "Sharp; type of accent" , "Perspicacious" , "(Of an angle) less than 90 degrees" .)