鎮
チン, しず.める, しず.まる, おさえ, しげ, じん, ちか, しん

tranquilize, ancient peace-preservation centers

JLPT1 G7 S18 F1617

As per 眞# (fullness) + 金 metal → heavy metal weight, fully able to hold/*weigh down* objects → *suppress*; *quell*; *appease*; *soothe*; *quiet down*; *calm* (v.); *bring peace*.

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