博士【はかせ】
expert, learned person, doctor, PhD, Dr., instructor at the imperial court (ritsuryō period), pitch and length marks (to accompany a Buddhist liturgical chant, etc.)
博物館【はくぶつかん】
museum
博覧会【はくらんかい】
fair, exhibition, exposition
博愛【はくあい】
charity, benevolence, philanthropy, (love for) humanity, fraternity, brotherhood, brotherly love, love of fellow man