'anomalism' originates from Greek, specifically the word 'anōmalía' (ἀνωμαλία), where 'an-' meant 'not' or 'without' and 'homalos' (ὁμαλός) meant 'even' or 'level'. The English form was created by adding the suffix '-ism' to 'anomaly.'

'anōmalía' (Greek) passed into Late Latin and Old French as 'anomalie' and then into Middle English as 'anomaly'; in English, the derivative 'anomalism' was formed by attaching the suffix '-ism' to denote the state or condition of being anomalous.

Initially it meant 'unevenness' or 'deviation from the norm'; over time it has been used more generally to mean 'the state or instance of being anomalous' in scientific and general contexts.