the three divisions of the viscera (med.)
膲 is a rare medical term referring to the three visceral cavities or divisions in traditional Chinese medicine. Its standalone meaning is highly specialized and not used in everyday language.
膲 combines the flesh radical ⺼ with 焦, which likely provides the sound. The exact historical development is uncertain, but it is a phono-semantic compound used in medical terminology.
The flesh radical ⺼ suggests a body part, and 焦 (scorch) might evoke the heat or energy of internal organs. Picture the three visceral cavities as three heated chambers within the body.
For ショウ, imagine a doctor showing (ショウ) a diagram of the three visceral divisions: show -> ショウ, and the flesh radical reminds you it's about the body.