kind of tench
鱅 refers to a kind of tench, a freshwater fish. The meaning is a specific fish name with no broader conceptual center.
鱅 combines 魚 (fish) with 庸, which likely contributes the sound. The character was created to name a specific fish, the tench.
The left side is 魚 (fish), and the right side 庸 looks like a sturdy container. Imagine a tench, a kind of fish, being kept in a special tank shaped like 庸.
For ショウ, picture a show where a tench fish jumps through a hoop: show -> ショウ, and the fish is the star of the performance.