A charming accent (5)
I believe the answer is:
acute
'accent' is the definition.
(acute is a kind of accent)
'a charming' is the wordplay.
'charming' becomes 'cute' (I've seen this before).
'a'+'cute'='ACUTE'
(Other definitions for acute that I've seen before include "Sharp, angle or mind" , "Keen; severe" , "Very perceptive, having sharp mind" , "Sharp; type of accent" , "Sharp like angle" .)