pendant ornaments, earrings
璫 centers on decorative hanging jewelry, specifically pendant ornaments and earrings that dangle.
璫 combines 王 (jade/gem) with 當, which likely contributes the sound and may relate to the idea of something hanging or being appropriate. The exact historical development is uncertain.
The left side 王 (jade) suggests precious stone, and the right side 當 looks like a hanging ornament with a top hook and dangling parts. Picture a jade earring suspended from the ear.
For トウ, imagine a toe adorned with a dangling jade ring: toe -> トウ, and the pendant swings as you walk.