打更 解释：
◎ 打更 dǎgēng
[sound the night watches;patrol the streets at night and announce the watches] 旧时打梆子或敲锣巡夜报时(一夜分为五更,每更约两小时)
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国语辞典旧时把一夜分做五更，每到一更，巡夜者敲锣击梆以报时，称为「打更」。如：「北方有些城市仍然保有打更的传统，从晚上八时起至隔日清晨四时止。」近击柝
英语 to sound the night watches (on clappers or gongs, in former times)