a reed instrument
笙 refers to a traditional reed instrument, specifically a mouth organ with multiple pipes. The meaning is narrow and concrete, centered on this particular musical instrument.
笙 combines 竹 (bamboo) with 生, which likely contributes the sound. The character reflects the bamboo construction of this reed instrument.
The top part 竹 is bamboo, and the bottom 生 suggests something growing or producing sound. Picture a bamboo plant growing into a musical instrument: the bamboo pipes of a reed mouth organ.
For ショウ, imagine a show where a musician plays a bamboo reed instrument on stage: show -> ショウ, and the bamboo pipes produce the music.