ominous or sinister spirit, vigor
祲 centers on a supernatural force that can be either menacing or full of energy: an ominous spirit or a surge of vigor. The two meanings seem to split between a dark spiritual presence and a powerful vitality, without a single clear conceptual link.
祲 combines 示 (altar/spirit) with a phonetic component that likely contributed the reading シン. The exact historical development of the right side is uncertain, but the character is associated with ominous spiritual forces.
The left side 示 suggests a spirit or altar. The right side looks like a complex, unsettling shape—picture a dark, energetic force swirling around the altar, bringing either menace or raw power.
For シン, imagine a sinister spirit hissing 'shin' as it looms over the altar: shin -> シン, and the ominous presence fills the scene.
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