baby teeth, young child
齠 centers on the early stage of life when baby teeth appear, referring to a young child or the milk teeth themselves.
齠 combines 齒 (teeth) with 召, which likely provides the sound. The character specifically refers to the shedding of milk teeth and the age when that occurs.
The left side is a tooth 齒, and the right side 召 looks like a call to action. Imagine a young child being called to show off their new baby teeth.
For チョウ, picture a young child named Chou proudly showing their baby teeth: Chou -> チョウ, and the teeth are the focus.
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