needle juniper, (kokuji)
榁 is a Japanese kokuji for a needle juniper tree. Its meaning is specific to that tree and does not extend to other concepts.
榁 is a Japanese kokuji created by combining 木 (tree) with 室 (room, chamber), likely chosen for its sound むろ to represent the needle juniper tree.
A tree (木) that grows in a room-like (室) enclosure? Picture a needle juniper carefully cultivated in a garden room.
For むろ, imagine a needle juniper growing in a muro (室, room) — the tree is literally a 'room tree': むろ.
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