tribe of Scythians which invaded China during the Hsia dynasty
獯 refers to a specific historical tribe: the Scythians who invaded China during the Hsia dynasty. Its meaning is narrowly tied to that ancient ethnic group.
獯 combines the beast radical 犭 with 熏, which likely provides the sound. The character was created to name a specific foreign tribe, using the animal radical to mark it as an ethnic group perceived as outside Chinese civilization.
The beast radical 犭 hints at a wild or foreign group, and 熏 suggests smoke or influence. Picture a tribe emerging from the smoky steppes, marked by the animal-like radical.
For クン, imagine the tribe's leader named Kun, who led the invasion: Kun -> クン, and his name echoes the reading.
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