mixing rice into soup
糂 centers on the action of mixing rice into soup, creating a thick, porridge-like dish.
糂 combines 米 (rice) with 甚, which likely contributes the sound ジン and may suggest the idea of something substantial or thick, fitting the meaning of mixing rice into soup.
The left side is 米 (rice), and the right side 甚 looks like a container with a lid. Picture rice being poured into a pot of soup and stirred until thick.
For ジン, imagine mixing rice into soup to make a thick, gin-like consistency: gin -> ジン, and the rice thickens the soup.
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