obstruct
峺 centers on obstruction or blocking, likely in a physical or metaphorical sense. The given meaning 'obstruct' is the core idea.
峺 combines 山 (mountain) with 更, which may contribute a phonetic element. The exact historical development is uncertain, but the mountain radical suggests a connection to terrain or obstruction.
A mountain (山) with something hard (更) blocking the way: imagine a rocky mountain pass that obstructs your path.
For コ, picture a small child (子, こ) trying to climb the mountain but being obstructed by a big rock: 子 -> コ, and the obstruction stops the child.
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