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to become quiet; to quiet down; to quieten down
to calm down; to die down; to subside; to abate; to be suppressed
薬を飲んだら痛みがだんだん鎮まった。
The pain gradually subsided after I took the medicine.
群衆の怒りがなかなか鎮まらなかった。
The crowd's anger was slow to subside.
嵐が鎮まるまで家の中で待った。
I waited inside until the storm subsided.