one of the nine chief magistrates of ancient Athens, 1650s, from Greek arkhon "ruler," noun use of present participle of arkhein "to rule," from PIE *arkhein- "to begin, rule, command," a "Gk. verb of unknown origin, but showing archaic Indo-European features ... with derivatives arkhe, 'rule, beginning,' and arkhos, 'ruler' " [Watkins].