This rare kanji has no clear standalone meaning. Treat its meaning as uncertain.
穕 combines 禾 (grain) with 集 (gather). The exact historical development is uncertain, but it likely relates to gathering grain.
The left side 禾 suggests grain, and the right side 集 means gather. Picture grain being gathered together, though the exact meaning is unclear.
For ショウ, imagine a show of gathered grain: show -> ショウ, and the grain 禾 is collected 集 for display.
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