mound, used in place names
堽 centers on an earthen mound or raised ground, and it appears mainly in place names rather than everyday vocabulary.
堽 combines 土 (earth) with 罡, which likely contributes the sound コウ. The exact historical development of 罡 is uncertain, but the character as a whole points to an earthen mound.
The left side is 土 (earth), and the right side 罡 looks like a net (罒) over a mountain (山-like lower part). Picture a mound of earth piled up under a net, like a landmark in a place name.
For コウ, imagine a mound so large it could be a small hill: hill -> コウ (using the English word 'hill' as a close sound hook, though the vowel is slightly different). Picture the earth 土 mound rising like a hill.
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