ladle, one tenth of a go, dip
勺 centers on a small scooping tool: a ladle for dipping liquids, and by extension a small unit of volume (one tenth of a go).
勺 is a pictograph of a ladle or scoop, with the outer 勹 representing the bowl and the inner 丶 the handle or contents.
The outer 勹 is the curved bowl of a ladle, and the dot 丶 inside is a drop of liquid being dipped. Together they form 勺, a ladle.
For シャク, imagine a shack where a ladle hangs on the wall: shack -> シャク, and the ladle is used to dip water.
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