This rare kanji has no clear standalone meaning. Treat its meaning as uncertain.
The exact historical development of 秚 is uncertain. It visually combines 禾 (grain) and 半 (half), but the original meaning and component relationship are unclear.
With no clear meaning, picture a half-grown grain stalk: the left side 禾 is grain, and the right side 半 is half. This image may help remember the shape, but the meaning remains uncertain.
For ハン, imagine a half-grown grain stalk being cut in half: half -> ハン, and the grain 禾 is split by 半.