This rare kanji has no clear standalone meaning. Treat its meaning as uncertain.
穥 combines 禾 (grain) with 與, which likely contributes sound. The exact historical development and original meaning are uncertain.
With grain 禾 beside 與, picture an ancient ritual offering of grain, but the exact meaning is unclear.
For ヨ, imagine a yo-yo made of grain stalks: yo -> ヨ, and the grain 禾 is tied to the 與 shape.