This rare kanji has no clear standalone meaning. Treat its meaning as uncertain.
溙 is a rare character combining 氵 (water) with 泰. The exact historical development is uncertain.
The water radical 氵 beside 泰 suggests a connection to water, but the exact meaning is unclear. Picture a rare, ancient water-related character.
For タイ, imagine a tie floating on the water: tie -> タイ, and the water radical 氵 keeps it afloat.
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