iconoclast

Concise Oxford English Dictionary © 2008 Oxford University Press:
iconoclast /ʌɪˈkɒnəklast/

▶noun

• 1 a person who attacks cherished beliefs or institutions.

• 2 a person who destroys images used in religious worship, especially one belonging to a movement opposing such images in the Byzantine Church during the 8th and 9th centuries.

– derivatives
iconoclasm noun,
iconoclastic adjective,
iconoclastically adverb.

– origin C17: via med. L. from eccles. Gk eikonoklastēs, from eikōn ‘likeness’ + klan ‘to break’.