Possibly Harold's Dolly Mixture (5)
I believe the answer is:
lloyd
'possibly harold's' is the definition.
I can't judge whether this defines the answer.
'dolly mixture' is the wordplay.
'mixture' is an anagram indicator.
'dolly' is an anagram of 'LLOYD'.
Can you help me to learn more?
(Other definitions for lloyd that I've seen before include "Bridges perhaps" , "Welsh family name" , "Harold - - , silent comic" , "David - George, British PM nineteen sixteen to nineteen twenty two" , "David -- George, PM 1916-22" .)