This rare kanji has no clear standalone meaning. Treat its meaning as uncertain.
遧 combines the movement radical 辶 with 章, but the exact historical development and original meaning are uncertain.
The movement radical 辶 surrounds 章, a component associated with clear patterns or chapters. Picture a clear path unfolding step by step, but remember the meaning is uncertain.
For ショウ, imagine a show of clear patterns moving along a path: show -> ショウ, and the movement radical 辶 carries the pattern 章 forward.