'image-worshipping' is a Modern English compound formed from 'image' + 'worship'; 'image' ultimately comes from Latin 'imago' via Old French 'image', and 'worship' comes from Old English 'weorþscipe' (weorþ + -scipe).

'image' comes from Latin 'imago' → Old French 'image' → Middle English 'image'; 'worship' developed from Old English 'weorþscipe' (meaning 'worthiness' or 'honor') → Middle English 'worschip' → modern English 'worship'; the compound 'image-worship' and its verbal/adjectival forms arose in Modern English by combining the two elements.

Initially, the separate elements meant 'likeness, picture' (image) and 'worthiness/honoring' (worship); combined, the compound originally referred specifically to the religious practice of revering religious images, and it has retained that primary meaning while also gaining figurative senses such as 'idolizing images or people' in modern usage.