aristocracy UK /ˌæɹ.ɪˈstɒk.ɹə.si/US /ˌɛɹ.ɪˈstɑ.kɹə.si/ noun3 •The nobility, or the hereditary ruling class.That, then, which is called aristocracy in some countries and nobility in others arose out of the governments founded upon conquest. — 1791 •A class of people considered (not normally universally) superior to others. •Government by such a class, or a state with such a government. formsaristocracies