type of mushroom
茯 refers to a specific type of mushroom, used in traditional contexts. Its meaning is narrow and botanical, without broader abstract extensions.
茯 combines 艹 (grass/plant) with 伏, which likely provides the sound. The character was created to name a specific medicinal mushroom.
The top grass radical 艹 suggests a plant, and the bottom 伏 looks like a person lying down. Imagine a mushroom growing low to the ground, almost hidden like a person crouching in the grass.
For フク, picture a mushroom that looks like a fluffy cushion: 'fluff' cues フク, and the mushroom is soft and round.
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