table, desk, stand
桌 centers on a raised flat surface used for work or holding things: a table, desk, or stand.
桌 is a phono-semantic compound: the top ⺊ (a variant of 卜) likely hints at the sound, while the bottom 杲 (bright) may have been chosen for its visual resemblance to a table-like structure. The exact historical development is uncertain.
The top ⺊ looks like a flat tabletop, and the bottom 杲 suggests a wooden frame with legs (木) and a bright surface (日). Together they form a sturdy table or desk.
For タク, imagine placing a tack on the table to mark a spot: tack -> タク, and the table holds it steady.
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