president: [14] A president is etymologically simply someone who ‘presides’. The word comes via Old French president from Latin praesidēns, the present participle of praesidēre ‘superintend’ (it literally meant ‘sit in front of’ – it was formed from the prefix prae- ‘before’ and sedēre ‘sit’ – and it has given English preside [17]). Another Latin derivative was the noun praesidium ‘garrison, fortification’, which English has acquired via Russian prezídium as presidium [20]. => preside, presidium, sit[president etymology, president origin, 英语词源]