This rare kanji has no clear standalone meaning. Treat its meaning as uncertain.
椖 combines 木 (tree/wood) with 房, which likely contributes the sound ホウ. The exact historical development and original meaning are uncertain.
The left side is 木 (tree/wood), and the right side is 房 (room/chamber). Picture a wooden chamber or a tree growing beside a room, but its exact meaning is unclear.
For ホウ, imagine a wooden house (木) with a room (房) where someone shouts 'Ho!' to test the echo: Ho -> ホウ.
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