uncle, youth
叔 centers on a younger male relative, specifically a younger uncle or a youth. The meaning 'uncle' is the primary application, while 'youth' reflects the junior status implied by the character.
叔 combines 尗 (a plant or bean shape, possibly related to gathering) with 又 (hand), suggesting a hand picking or gathering. The exact historical link to 'uncle' or 'youth' is uncertain; it may have been a phonetic loan or a semantic extension.
The left side 尗 looks like a small plant or bean, and the right side 又 is a hand. Imagine a young uncle helping a youth pick beans in the garden.
For シュク, picture a young uncle shaking a bag of beans: shake -> シュク, and the hand 又 is shaking the plant 尗.
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