high & level, lofty, bald, dangerous
兀 centers on a stark, exposed height: something towering and bare, like a bald peak or a precarious, dangerous elevation.
兀 is a pictograph of a person with a flat top, suggesting a high, bare, or bald appearance. The exact historical development is uncertain, but the image of a towering, exposed shape is consistent.
The top horizontal line 一 sits above the legs 儿 like a flat, bald head on a tall body. Picture a dangerous, lofty cliff with nothing on top—just bare and high.
For コツ, imagine a bald monk meditating on a dangerous peak, and he keeps his focus by repeating a sharp, short 'kotsu' sound. The sound 'kotsu' cues コツ while the scene matches the bare, lofty meaning.
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