tree
栻 is a rare kanji that centers on a tree, likely referring to a specific type of tree or wooden object. Its standalone meaning is narrow and not widely used in modern Japanese.
栻 combines 木 (tree) with 式, which likely contributes a phonetic element. The exact historical origin is uncertain, but it probably named a particular tree or wooden implement.
A tree 木 with a distinctive form 式: picture a tree shaped like a ceremonial form or pattern, making it a special kind of tree.
For チョク, imagine a tree that grows perfectly straight, like a chok line drawn with a ruler: chok -> チョク, and the tree stands upright.
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