type of vine
薜 refers to a type of vine, specifically a climbing or creeping plant. Its meaning is narrow and botanical.
薜 combines the grass radical 艹 with 辟, which likely contributes a phonetic element. The character is used for a specific vine name.
The grass radical 艹 on top of 辟 suggests a plant. Imagine a vine with many leaves (艹) climbing over a wall-like structure (辟).
For ヘイ, picture the vine growing over a hedge shaped like the letter H: H -> ヘイ, and the vine covers it completely.
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