irregular teeth
齬 centers on teeth that are not aligned properly: irregular, crooked, or uneven teeth. The idea is a lack of smooth fit, like teeth that do not meet neatly.
齬 combines 齒 (teeth) with 吾, which likely provides the sound. The character expresses the idea of teeth that are irregular or do not meet properly.
The left side is 齒 (teeth), and the right side 吾 looks like a mouth with something stuck inside. Picture a set of teeth that are crooked and irregular, like a mouth that cannot close smoothly.
For ゴ, imagine a person with irregular teeth trying to say 'go' but the sound comes out garbled because their teeth are not aligned: go -> ゴ.
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