'apotheosis' originates from Greek, specifically the word 'apotheōsis' (ἀποθέωσις), where the prefix 'apo-' meant 'away/from' and 'theos' meant 'god'.

'apotheosis' passed into Latin as 'apotheosis' and was borrowed into English (via Late Latin and French influence) with the same form; it entered English use in the 16th–17th centuries from these classical sources.

Initially, it meant 'the act of making someone a god' (literal deification); over time it also acquired a figurative sense of 'the highest point or perfect example' and that broader meaning remains common.