type of mugwort
薛 refers to a specific type of mugwort, a plant in the Artemisia genus. Its meaning is narrow and botanical, without broader abstract extensions.
薛 combines the grass radical 艹 with a phonetic component historically related to 辥, which likely provided the sound. The character was used as a plant name and also as a surname in Chinese contexts.
The top grass radical 艹 signals a plant. The right side 辛 (spicy, bitter) hints at the strong, bitter aroma of mugwort. Together, 薛 is the bitter mugwort plant.
For セツ, imagine a set of mugwort bundles drying in the sun: set -> セツ, and each set is a harvest of the bitter herb.
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