This rare kanji has no clear standalone meaning. Treat its meaning as uncertain.
苠 combines 艹 (grass/plant) with 民 (people). The exact historical development and original meaning are uncertain.
The top 艹 suggests a plant, and the bottom 民 suggests people. Imagine a plant that grows abundantly among people, but its exact meaning is unclear.
For ビン, picture a bin full of this mysterious plant: bin -> ビン, and the plant grows thickly inside.