Traditionally, the radical 58 has the meaning: pig's head, or pig's snout. The trainer always uses it as “hand”, i.e. as a variant of , which shows a hand with the fingers pointing to the left. This often appears to be etymologically justified.
Image of a hand 一 forearm 丨 and pulse 丶. It was originally also the distance of one inch (Length: 1 ts'wun = 3.72 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".
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