Prankster's lilting accent, not British (5)
I believe the answer is:
rogue
'prankster's' is the definition.
(thesaurus)
'lilting accent not british' is the wordplay.
'lilting accent' becomes 'brogue' (I've seen this before).
'not' is a deletion indicator.
'british' becomes 'b' (abbreviation e.g. in 'BBC').
'brogue' with 'b' taken away is 'ROGUE'.
(Other definitions for rogue that I've seen before include "Unprincipled man" , "Dishonest man" , "Dishonest chap; solitary (elephant)" , "Miscreant" , "Scamp" .)