iconoclasmEnglishOxford New American Dictionaryiconoclasm /īˈkänəˌklazəm, aɪˈkɑnəˌklæzəm / ▸ noun 1 the action of attacking or assertively rejecting cherished beliefs and institutions or established values and practices. 2 the rejection or destruction of religious images as heretical; the doctrine of iconoclasts. – ORIGIN late 18th century : from iconoclast, on the pattern of pairs such as enthusiast, enthusiasm.