'bankings' derives from the modern English noun 'banking' (formed by adding the suffix '-ing' to 'bank'), where 'bank' refers to the business or place of a bank.

'banking' developed from Middle English 'bank(e)', borrowed from Old Italian 'banca' meaning 'bench' or 'table' used by money-changers; over time 'banca/bank' came to mean a money-dealing establishment and then the verb 'to bank' and the noun 'banking' for its activities; 'bankings' is simply the plural form of 'banking' in modern English.

Initially 'banca' literally meant 'bench' (the bench used by money-changers); it evolved into 'bank' meaning a money-dealing place and then into 'banking' meaning the business or practice of banking; the plural form 'bankings' refers to multiple instances or types of that business or activity.