This rare kanji has no clear standalone meaning. Treat its meaning as uncertain.
禌 combines 示 (altar, spirit) with 兹, which may contribute sound. The exact historical development is uncertain.
The left side 示 suggests a spiritual or ritual context, and the right side 兹 looks like a tangled thread. Picture an obscure ritual object used in ancient ceremonies, but its exact purpose is unclear.
For シ, imagine a mysterious shrine (示) where a shaman whispers 'she' (シ) while handling the tangled ritual threads (兹).