resound, reverberate
哄 centers on loud, filling sound: a noise that resounds or reverberates through a space, often from many voices or a collective outburst.
哄 combines 口 (mouth) with 共, which likely contributes the sound and the idea of togetherness, suggesting many mouths producing a resounding noise.
Many mouths (口) together (共) create a loud, reverberating sound that fills the air.
For コウ, imagine a crowd's roar echoing through a hall: the hollow 'koh' sound cues コウ as the noise resounds.
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