'assecurator' originates from Medieval Latin, specifically the word 'assecurator', from the verb 'assecurare' (to make safe or secure), where the prefix 'ad-' (assimilated to 'as-') meant 'to/toward' and 'securus' meant 'safe'.

'assecurare' (Medieval Latin) influenced Old French forms such as 'assecurer' and entered legal and technical English usage as 'assecuration' (insurance) and the agent noun 'assecurator' in legal/older texts.

Initially it meant 'one who makes safe' in a general sense; over time the meaning narrowed to the specific modern sense of 'insurer' or 'underwriter'.