yellow fish (herring) eggs (sushi), (kokuji)
鯑 is a Japanese kokuji that refers specifically to yellow fish eggs, especially herring roe used in sushi. Its meaning is narrow and concrete, centered on this single food item.
鯑 is a kokuji created in Japan by combining 魚 (fish) with 希, likely chosen for its sound to represent kazunoko (herring roe). The exact historical development is uncertain.
The left side 魚 means fish, and the right side 希 looks a bit like a cluster of tiny eggs. Picture a fish surrounded by its yellow roe: 鯑 is those fish eggs.
For かずのこ, imagine a sushi chef counting the eggs: 'Kazu no ko' sounds like 'number of children,' and the chef is counting the tiny yellow fish eggs on the sushi.
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