'colossi' originates from Latin, specifically the plural form 'colossi' of 'colossus', which derives from Ancient Greek 'kolossós', where 'kolossós' meant 'a giant statue'.

'kolossós' passed into Latin as 'colossus' (plural 'colossi'), entered Middle English as 'coloss'/'colossus', and eventually established the modern English singular 'colossus' with the learned plural 'colossi'.

Initially, it meant 'a gigantic statue', but it broadened figuratively to refer to 'a person or thing of enormous size, power, or importance'.