Word Origin & History
"overseer," 1640s, Amer.Eng., from Du. baas "a master," M.Du. baes, of obscure origin. If original sense was "uncle," perhaps it is related to O.H.G. basa "aunt," but some sources discount this theory. The Du. form baas is attested in English from 1620s as the standard title of a Dutch ship's captain.
The word's popularity in U.S. may reflect egalitarian avoidance of master as well as the need to distinguish slave from free labor. The verb is from 1856. The slang adjective meaning "excellent" is recorded in 1880s, revived, apparently independently, in teen and jazz slang in 1950s.
"protuberance, button," c.1300, from O.Fr. boce "a hump, swelling, tumor" (12c., Mod.Fr. bosse), from either Frank. *botija or V.L. *bottia, both of uncertain origin.