shout
咻 centers on a loud vocal outburst: a shout or cry. The single given meaning is straightforward and concrete.
咻 combines 口 (mouth) with 休, which likely contributes the sound. The character is rare, and its exact historical development is uncertain.
A mouth 口 beside a resting person 休: imagine someone suddenly shouting to wake the resting person up.
For ク, picture a coo-coo bird shouting from its nest: coo -> ク, and the sound bursts from its mouth 口.
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