Blasphemous (7)
I believe the answer is:
profane
'blasphemous' is the definition.
(similar in meaning)
This is all the clue.
(Other definitions for profane that I've seen before include "Secular, not religious" , "Contemptuous of sacred things" , "Secular; obscene" , "Irreverent - pagan" , "Secular; blasphemous" .)