precipitous, inaccessible place, impregnable position, steep place, sharp eyes
険 centers on steep, dangerous terrain: a precipitous cliff or an inaccessible, impregnable position. The sense of sharp eyes extends this idea to a piercing, penetrating gaze that is hard to approach.
険 combines the hill radical ⻖ with the phonetic component 㑒 (ケン), suggesting a steep, dangerous hill or cliff. The exact historical development of 㑒 is uncertain, but the phono-semantic structure is clear.
The left side ⻖ is a hill, and the right side 㑒 looks like a person peering over a sharp edge. Picture standing on a precipitous cliff, looking down with sharp eyes at the inaccessible steep place below.
For ケン, imagine a steep cliff that looks like a giant canine tooth: canine -> ケン, and the sharp, precipitous shape matches the kanji's meaning.
danger; peril; hazard
insurance
adventure; venture
precipitous; rugged; inaccessible; impregnable; steep
dangerous; perilous; threatening; stormy; volatile; tense; critical; serious
cruel; hard-hearted; harsh; unkind
crafty; tricky; sly; wily; treacherous; underhand
steepness; steep place
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