phoneme only, (kokuji)
弖 is a rare kokuji used only for its sound value, without a standalone meaning. Its meaning is uncertain and context-dependent.
弖 is a Japanese-made kokuji, likely created by adding a horizontal stroke to 弓 to represent the sound テ. The exact historical development is uncertain.
弖 looks like a bow (弓) with an extra line, but it has no inherent meaning. Think of it as a placeholder shape for the sound テ.
For テ, imagine the bow (弓) being drawn taut, and the extra stroke at the bottom represents the tension (テンション) of the string: tension -> テン, shortened to テ.
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