destroy, steal
勦 centers on forceful removal: destroying something completely or taking it away by stealth. The two given meanings—destroy and steal—both involve eliminating or removing something, whether openly or secretly.
勦 combines 巢 (nest) and 力 (strength/power). The exact historical development is uncertain, but it likely expresses the idea of using force to destroy or take from a nest, aligning with the meanings of destroy and steal.
Imagine using force (力) to smash a nest (巢) and steal its contents. The nest is destroyed and its treasures are taken—that's 勦.
For ソウ, picture a thief stealing a nest and then sewing it back together to hide the crime: sew -> ソウ, and the nest is secretly destroyed.
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complete annihilation