The radical shikabane has the meaning: corpse 尸. But because of its use in tail 尾, buttocks 尻 or urine 尿, it is generally considered to mean "buttocks".
Image of a hand 一 forearm 丨 and pulse 丶. It was originally also the distance of one inch (Length: 1 SUN = 3.03 cm) from the hand's palm to the pulse. This also stood for a small amount. In the mnemonic, it is used as "skillful hand" and partly also "to measure".
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