binary star

two stars that revolve around a common centre 双星（环绕一共同中心旋转的两颗星）.

billet-doux, billfold, billhook, billiard-, billiards, billion, billow, billowy, billposter (also billsticker), billy, billy-goat, billy-oh (also billy-o), biltong, bimetallic, bimetallism, bimonthly, bin, binary, binary digit, binary notation system, bind, binder, bindery, binding, bindweed, bine, binge, bingo, binnacle, binoculars, binomial, biochemical, biochemist, biochemistry, biodegradable, biographer, biographic, -ical, biography, biological, biological control,