1837, from Greek hoi polloi (plural) "the people," literally "the many" (plural of polys, from PIE root *pele- (1) "to fill"). Used in Greek by Dryden (1668) and Byron (1822), in both cases preceded by the, even though Greek hoi means "the," a mistake repeated often by subsequent writers who at least have the excuse of ignorance of Greek. Ho "the" is from PIE *so- "this, that" (nominative), cognate with English the and Latin sic. From the adjective agoraios "pertaining to the agora; frequenting the market" Greek had hoi agoraioi "loungers in the market, loafers, common, low men."
undergraduate honorary society, 1776, from initials of Greek philosophia biou kybernētēs "philosophy, guide of life."
c. 1600, "victory involving one's own ruin," translating Greek Kadmeia nikē, from Cadmus (Greek Kadmos), legendary hero-founder of Thebes in Boeotia and bringer of the original sixteen-letter alphabet to Greece. The term probably is a reference to the story of Cadmus and the "Sown-Men," who fought each other till only a handful were left alive. Compare Pyrrhic (adj.1).
1963, short for Papanicolaou (1947) in reference to George Nicholas Papanicolaou (1883-1962), Greek-born U.S. anatomist who developed the technique of examining secreted cells to test for cancer.
1590s, originally, as in Greek and Roman mythology, the last and worst age of the world; the archaeological sense of "period in which humans used iron tools and weapons" is from 1866 (earlier in this sense iron period, 1847).
(plural legomena), "word occurring only once," Greek, literally "once said," from hapax "once only" + legomenon, neuter passive present participle of legein "to say," from PIE root *leg- (1) "to collect, gather," with derivatives meaning "to speak (to 'pick out words')."
Latin, literally "he (the master) said it," translation of Greek autos epha, phrase used by disciples of Pythagoras when quoting their master. Hence, "an assertion made without proof, resting entirely on the authority of the speaker" (1590s), ipsedixitism "practice of dogmatic assertion" (1830, Bentham), etc.