Wicked one's carrying dodgy opium (7)
I believe the answer is:
impious
'wicked' is the definition.
('impious' is associated in meaning with 'wicked')
'one's carrying dodgy opium' is the wordplay.
'one's' becomes 'is' (roman numeral).
'carrying' indicates putting letters inside.
'dodgy' is an anagram indicator.
'opium' anagrammed gives 'mpiou'.
'is' enclosing 'mpiou' is 'IMPIOUS'.
(Other definitions for impious that I've seen before include "9 [DEMON]" , "Showing disrespect for a god" , "Irreverent; wicked" , "Lacking veneration or respect" , "Wicked, profane" .)