teeth grown in old age
齯 refers specifically to teeth that appear or regrow in old age, a rare concept tied to late-life dental changes.
齯 combines 齒 (tooth) with 兒, which likely contributes the sound and may relate to the idea of a child or new growth, suggesting teeth appearing anew in old age.
The left side 齒 means tooth, and the right side 兒 looks like a child. Imagine an old person growing a new tooth as if they were a child again.
For ゲイ, picture an old person saying 'Gee, I grew a new tooth!' The 'Gee' sound cues ゲイ, and the surprise fits the rare event of teeth in old age.
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