poison: [13] Etymologically, poison is simply something you ‘drink’. The word comes via Old French poison from Latin pōtiō ‘drink’ (source also of English potion), a derivative of the verb pōtāre ‘drink’ (from which English gets potable). The specialization in meaning from ‘drink’ to ‘poisonous drink’ took place in classical Latin, but the further progression to ‘any poisonous substance’ is a later development. Another probable relative is pot. => potable, potion, symposium[poison etymology, poison origin, 英语词源]