large hand bell
鐸 centers on a large hand bell, a resonant metal instrument rung by shaking or striking.
鐸 combines 金 (metal) with 睪, which likely contributes the sound and may relate to the bell's resonant quality. The exact historical development of 睪 in this context is uncertain.
The left side 金 is metal, and the right side 睪 looks like a bell with a clapper inside. Picture a large metal hand bell being rung.
For タク, imagine the bell making a loud 'taku' sound when struck: taku -> タク, and the metal bell rings out.
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