'athanor' originates from French, specifically the word 'athanor', ultimately from Arabic 'al‑tannūr' (also spelled 'tanūr'), where 'al-' meant 'the' and 'tannūr' meant 'oven'.

'athanor' passed through Medieval Latin and Old French as forms like 'athanor' (also attested as 'athanor') and was borrowed into English from French (usage attested from Early Modern English onward) as the specialized term for an alchemical furnace.

Initially the root referred broadly to an 'oven' in Arabic; in European alchemical contexts it narrowed to mean a particular closed furnace used to maintain steady heat for alchemical operations.