This rare kanji has no clear standalone meaning. Treat its meaning as uncertain.
The exact historical development of 屽 is uncertain. It visually combines 山 (mountain) and 干, but the original meaning and component function are unclear.
With no clear meaning, picture a mountain 山 beside a shield 干: a mysterious ancient character whose story is lost.
For カン, imagine a can sitting on a mountain: can -> カン, a simple hook for this rare kanji.
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