'mythologizer' originates from English, specifically formed from the verb 'mythologize' with the agentive suffix '-er'. 'Mythologize' ultimately comes from Late Latin/French forms related to 'mythologia', where the Greek roots 'mythos' meant 'story' and 'logos' meant 'word' or 'study'.

'Mythologize' was influenced by Late Latin/Medieval Latin (e.g. 'mythologizare') and Old French ('mythologiser'), derived from Classical Greek 'mythologia' (μυθολογία). Over time the verb entered English and the agentive suffix '-er' produced 'mythologizer'.

Initially connected to 'telling or studying myths' (the sense of 'mythology'), it evolved into the verb sense 'to represent or treat something as myth' and thus the agent noun now means 'one who mythologizes' or 'one who creates or attributes mythic status'.