Difficult puzzle about Earl with blown-up lilo (10)
I believe the answer is:
rebellious
'difficult' is the definition.
(thesaurus)
'puzzle about earl with blown-up lilo' is the wordplay.
'puzzle' becomes 'rebus' (I've seen this before**).
'about' means one lot of letters goes inside another.
'earl' becomes 'e'.
'with' means one lot of letters go next to another.
'blown up' is an anagram indicator.
'lilo' anagrammed gives 'llio'.
'e'+'llio'='ellio'
'rebus' placed around 'ellio' is 'REBELLIOUS'.
(Other definitions for rebellious that I've seen before include "Unruly" , "Difficult to control, unmanageable" , "Resisting authority" , "Defiant" , "Boxers were once so" .)