malt, (kokuji)
糀 centers on malt, specifically the mold-inoculated grain used in Japanese fermentation. It is a kokuji created in Japan for this concept.
糀 is a Japanese kokuji combining 米 (rice) and 花 (flower), referring to the flower-like mold growth on rice used to make kōji malt.
Rice 米 with flower 花: imagine rice grains blooming with mold like flowers, producing malt.
For こうじ, picture a koji mold starter blooming on rice like a flower: kōji -> こうじ.
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