type of oak, (kokuji)
椡 refers specifically to a type of oak tree (くぬぎ). As a kokuji, it was created in Japan for this native word and has no broader abstract meaning.
椡 is a kokuji (Japanese-made character) combining 木 (tree) with 到, which likely contributes the sound くぬぎ. It was created to represent the kunugi oak.
The tree radical 木 on the left marks this as a type of tree. The right side 到 suggests arriving at the specific oak species: 椡 is the kunugi oak.
For くぬぎ, imagine a cool new tree you discover: 'Cool new tree!' sounds like くぬぎ, and it's the kunugi oak.
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