wild dog (not very large), lock-up
犴 centers on a wild dog-like animal, specifically a smaller wild canine, and by extension a place of confinement or lock-up, possibly from the idea of caging such an animal.
犴 combines the animal radical 犭 with 干, which may have contributed a phonetic element. The exact historical development is uncertain, but the character is associated with a wild dog and later a prison or cage.
A wild dog 犭 is kept behind a dry, shield-like barrier 干, like a lock-up or cage for a small fierce animal.
For カン, imagine a can (カン) used to lock up a small wild dog: the can -> カン, and the dog is confined inside.
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