Badgers, bald eagles, bearcats, bears, beavers, bees, bengals, bisons and black bears are team nicknames. Bluejays, bobcats, braves, broncos, bruins, buccaneers, buffaloes and bulldogs are team nicknames.
Backstroke swimming, Badminton, balance beam gymnastics, Baseball, Basketball, beach volleyball, biathlon, billiards, bobsledding, bocce, bowling, boxing, breaststroke swimming, butterfly swimming are sports. They begin with the letter b.
Bearcat is the mascot at the University of Cincinnati
Bolton Wanderers Football Club.
basil
Botany.
bigfoot
Brunhilde is perhaps the longest. But that is just for English language.
A nine letter word using those letters is boomerang.
bumble bees
bibliography
bounce
No Legendary Pokemon begin with the letter B.
boris
Backrushes.
BIJJIGGLEHIGGLE
Banff
Boston
BermudaBostonBarbadosBerlinBrussels
Barn
Benson