This rare kanji has no clear standalone meaning. Treat its meaning as uncertain.
昹 combines 日 (sun) and 永 (long, eternal), but the exact historical development and original meaning are uncertain.
The sun 日 beside 永 (eternity) could suggest an endless day, but since the meaning is unclear, treat it as a rare character with an unknown sense.
For アイ, imagine an eye (アイ) staring at the sun 日 for an eternity 永: eye -> アイ, but the sun never sets.
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