'anti-ethnicity' originates from Modern English composition combining the prefix 'anti-' and the noun 'ethnicity'. 'anti-' ultimately comes from Greek 'anti' meaning 'against', and 'ethnicity' derives from Greek 'ethnos' meaning 'nation, people' via later linguistic developments.

'ethnos' (Greek) gave rise to 'ethnikos' (Greek) and then to forms in Latin and Modern European languages (e.g. French 'ethnique'), leading to the English adjective 'ethnic' and the noun 'ethnicity'. The productive prefix 'anti-' (from Greek 'anti') has long been used in English to form compounds (e.g. 'anti-war'), and the compound 'anti-ethnicity' is a modern English formation combining these elements.

Initially, 'ethnos' meant 'nation' or 'a people'; over time 'ethnicity' came to mean shared cultural identity or group membership. 'Anti-ethnicity' has developed as a modern term meaning opposition to ethnicity as a category or hostility toward ethnic groups.