to supervise, to confine a government establishment
譼 centers on official oversight: supervising people or activities, and confining or controlling a government establishment. Both meanings share the idea of authoritative watchfulness.
譼 is a rare character. It visually combines 言 (speech) with an upper element that includes 臣 (minister/official) and 罒 (net), suggesting official speech or oversight. The exact historical development is uncertain.
The bottom 言 (words) under the watchful eye of an official (臣) and a net (罒) suggests using speech to supervise and confine, like an inspector's report that keeps a government office in check.
For カン, imagine a supervisor who can confine any rule-breaker: can -> カン, and the official's words (言) have the power to supervise.
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