An appealing accent (5)
I believe the answer is:
acute
'accent' is the definition.
(acute is a kind of accent)
'an appealing' is the wordplay.
'an' becomes 'a'.
'appealing' becomes 'cute' (I've seen this in another clue).
'a'+'cute'='ACUTE'
(Other definitions for acute that I've seen before include "Shrewd; severe" , "Severe, penetrating" , "Critical, serious" , "Short and severe" , "Canny" .)