This rare kanji has no clear standalone meaning. Treat its meaning as uncertain.
The exact historical development of 曃 is uncertain. It visually combines 日 (sun) with 逮, but the original meaning and component function are unclear.
With no clear meaning, picture the sun 日 beside the complex 逮 shape as a mysterious ancient symbol whose sense has been lost over time.
For タイ, imagine a tie (ネクタイ) draped over the sun 日 and the 逮 component, as if the kanji itself is tied to an unknown meaning: tie -> タイ.
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