To commit blasphemy; to speak against God or religious doctrine.
To speak of, or address, with impious irreverence; to revile impiously (anything sacred).
To calumniate; to revile; to abuse.
An act of irreverence or contempt toward a god or toward something considered sacred; an impious act, utterance, view, etc.
That imam said that drawing the prophet Muhammad is a form of blasphemy.
(by extension) An act of irreverence towards anything considered inviolable; the act of disregarding a convention.