to rely on, depend on, evidence, proof
凴 centers on leaning on something for support: relying on or depending on a person or thing. The evidence and proof senses extend from the idea of relying on facts or documents to establish something.
凴 is a variant form of 憑, combining 馮 (which likely contributes the sound) with 几 (a low table or support), reinforcing the idea of leaning or depending on something. The exact historical development is uncertain.
The top 馮 looks like a horse 馬 standing on ice 冫, and the bottom 几 is a small table. Imagine a horse slipping on ice and leaning heavily on a table for support—that's relying on something.
For ヒョウ, picture a hyō (雹, hail) storm forcing you to rely on a sturdy table for shelter: hyō -> ヒョウ, and you depend on that table to stay safe.
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