Used only in 磅礴 ('boundless, majestic'), nearly always in the set phrase 气势磅礴 ('of grand, imposing momentum'). It describes mountains, rivers, music, and writing of overwhelming scale.
Supplies the sound on the right: 薄 in its bó reading gives the pronunciation. Its sense of 'pressing close, surging against' also faintly suits the idea of an overwhelming force.
