What is the origin of cynosure?
In Greek Kynósoura means “dog’s tail” and is also the name of the constellation Ursa Minor (also known as the Lesser Bear, Little Bear, and especially in American usage, the Little Dipper). The first element of Kynósoura is the genitive singular of the Greek noun kúōn “dog, bitch, shepherd dog, watchdog.” Greek kúōn (and its stem kun-) come a very wide spread Proto-Indo-European noun kúwōn (stems kwon-, kun-) “dog,” source of Sanskrit śvā́ (also śuvā́) (stem śun-), Old Prussian sunis, Germanic (German) Hund “dog,” (Old English) hund, (English hound). Greek ourā́ “tail” is akin to Greek órrhos “rump” (from orso-) comes from Proto-Indo-European orsos “buttocks, rump, tail,” source of Germanic (German) Arsch and English arse (ass in American English). Cynosure entered English at the end of the 16th century.