This rare kanji has no clear standalone meaning. Treat its meaning as uncertain.
堍 combines 土 (earth) with 兔 (rabbit), but its historical origin and meaning are uncertain. It may be a variant or rare character with no widely attested etymology.
The left side is earth 土 and the right side is a rabbit 兔. Picture a rabbit burrowing into the earth, but remember that the actual meaning is uncertain.
For ト, imagine a toe (ト) poking out of the rabbit's burrow in the earth: toe -> ト.
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