potent: [15] Latin posse (source of English posse and possible) meant ‘be able or powerful’. It was a conflation of an earlier verbal phrase potis esse ‘be able’. The precursor of posse was Old Latin *potēre, whose present participle potēns survived to become the present participle of posse. And its stem form potent- has given English potent, potentate [14], and potential [14]. Power also comes from *potēre. => posse, possible, potentate, potential, power[potent etymology, potent origin, 英语词源]