'annihilable' originates from Modern English, specifically the adjective formed from the verb 'annihilate', which ultimately comes from Latin 'annihilare', where 'ad-' meant 'to' and 'nihil' meant 'nothing'.

'annihilable' developed from the Modern English verb 'annihilate' (from Middle French/Latin paths), where Latin 'annihilare' ('ad-' + 'nihil') passed into late Latin and Old/Middle French as forms like 'anihiler'/'annihiler', then into English as 'annihilate', and finally the adjective form 'annihilable' was formed in English.

Initially the root meant 'to reduce to nothing' (literally 'to make nothing'), and over time this sense remained but specialized into meanings such as 'capable of being completely destroyed' in adjectival use.