This rare kanji has no clear standalone meaning. Treat its meaning as uncertain.
獖 combines the animal radical 犭 with 賁, which likely contributes the sound. The exact historical development and original meaning are uncertain.
The animal radical 犭 suggests a creature, but the meaning is unclear. Picture a mysterious beast hiding behind the complex shape 賁.
For フン, imagine a fun, fuzzy animal making a funny sound: fun -> フン, and the beast 獖 is having fun.
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