The accent of a big-headed rascal? (6)
I believe the answer is:
brogue
'the accent' is the definition.
(I've seen this before)
'a big-headed rascal?' is the wordplay.
'a big-headed' becomes 'b' (this could be a standard abbreviation of which I'm unaware).
'rascal?' becomes 'rogue' ('rogue' can be a synonym of 'rascal').
'b'+'rogue'='BROGUE'
'of' acts as a link.
Can you help me to learn more?
(Other definitions for brogue that I've seen before include "Footprint could be left by this" , "Worn" , "Decorated shoe; accent" , "Oxford" , "Patterned shoe, accent" .)