to change the time on your clocks to an hour earlier, at an officially chosen time of year

Don't forget to turn the clocks back tonight. 今晚别忘了把钟拨慢一小时。

We lose an hour of evening light when we turn the clocks back.

Remember that you need to turn the clocks back an hour before you go to bed.

I love it when we put the clocks back because we get an extra hour of sleep.

Sorry, what time is it there? We've just put the clocks back, but I don't remember when your country does it.

See also: clock noun (TIME)