'banalize' originates from French, specifically the adjective 'banal', combined with the suffix '-ize' (from Greek -izein via Latin/French) where 'banal' meant 'common, ordinary' and '-ize' meant 'to make or become'.

'banal' came into English from French 'banal' (from Old French 'ban' meaning a public proclamation or compulsory usage tied to a lord's 'ban'), and English later formed 'banalize' by adding the productive verb-forming suffix '-ize' to express 'make banal'.

Initially related to the idea of commonness or obligations associated with 'ban' (hence 'common, customary'), but over time the sense shifted to 'ordinary' or 'trite'; 'banalize' now means 'to make ordinary or trite'.