'annuller' originates from Latin, specifically the verb 'annullare', where the element 'ad-' (assimilated to 'an-') meant 'to' and 'nullus' meant 'none' or 'nothing'.

'annuller' changed from Middle English/Old French forms such as Middle English 'annullen' and Old French 'anuller', which in turn came from Latin 'annullare'; the modern English agent noun was formed by adding the suffix '-er' to the verb 'annul'.

Initially the Latin root meant 'to make into nothing' (to nullify); over time this core sense remained, and English developed the agent noun 'annuller' meaning 'one who or that which annuls'.