ball (sphere) / (basebal) ball (pitch that falls outside the strike zone)

bowl

Short for ボール紙 (bōru-gami): non-corrugated cardboard, pasteboard / Short for 段ボール (danbōru): corrugated cardboard

ball (formal dance event)

boat; rowboat

Cape Verde (an archipelago and country in West Africa)

(music) an oboe

volcano

bone / (onomatopoeia) kaboom / (onomatopoeia) boing / (onomatopoeia) bong

board (long, flat object) / board (a long piece of wood used in construction) / board (a committee)