stony
墝 centers on stony, hard, and barren ground. It describes land that is rocky and difficult to cultivate.
墝 combines 土 (earth, soil) with 堯, which likely contributes the sound and may relate to high or hard ground. The exact historical development is uncertain.
The left side 土 is earth, and the right side 堯 looks like a pile of hard, stacked rocks. Picture a field of stony soil where nothing grows.
For コウ, imagine a stony field so hard that even a crow (コウ) cannot peck at it. The crow's call 'koh' cues コウ while the barren ground stays stony.
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